[HN Gopher] That UPS you bought for your home server may not be ...
___________________________________________________________________
That UPS you bought for your home server may not be as useful as
you think
Author : LinuxBender
Score : 173 points
Date : 2020-08-10 14:08 UTC (8 hours ago)
(HTM) web link (fitzcarraldoblog.wordpress.com)
(TXT) w3m dump (fitzcarraldoblog.wordpress.com)
| mprovost wrote:
| This reminded me of James Hamilton's (the AWS datacentre guru)
| writeup of the power outage at the 2013 SuperBowl. Specifically
| how the default configuration of backup generators is often to
| protect themselves, even if that means shutting down the things
| they are meant to keep running. In my own experience running a
| reasonably sized datacentre I was often surprised at how UPSs and
| generators reacted to adverse conditions. One thing with power
| that you don't want is to be surprised. But it's difficult to
| test this equipment so it's mostly a learn as you go experience.
|
| https://perspectives.mvdirona.com/2013/02/the-power-failure-...
| mulmen wrote:
| My grade school neighbored a hospital. I recall occasional loud
| rumblings of the backup generators during recess, presumably
| they were tests. Legend was they came from a WWII submarine!
| Neat!
|
| Years later I had a tech support job in that hospital and all
| the PCs had small UPSs to keep them alive for the 30-60 seconds
| it took the big generators to come online.
|
| I never did get a chance to see the generator room.
|
| e: Another personal anecdote that is more relevant to the
| topic.
|
| I was working for a VOIP provider back when Hurricane Sandy hit
| NYC. Part of our production network was housed in a telecom
| building in Manhattan. We received daily updates on how many
| floors the flooding was from our equipment and about the fuel
| deliveries to the building backup generators. Apparently the
| generators were on the roof? I'd love to know more about the
| setup in that building because we had zero downtime.
| Fogest wrote:
| Working in a 911 call center this is how it worked for us.
| Except we had larger UPS's that could last probably 30-60
| minutes in the building and then a large external generator
| in a small building beside. You'd see stuff like the lights
| that weren't on the UPS's turn off for a few seconds before
| the main generator fired up.
| mark-r wrote:
| My current job refuses to replace old UPSs that have died,
| because they have a generator to keep the building powered
| in case of loss of power. But that doesn't keep your PC
| running for the moments it takes the generator to spin up.
| linsomniac wrote:
| Everything involved in 911 calls had special tagging to
| indicate it. Failure to go through appropriate review and
| approval processes before doing work on tagged equipment
| would create a Resume Generation Event.
| generatorguy wrote:
| Electrical Engineers would determine the settings for the
| electrical protection of a generator. Mechanical Engineers
| would determine the settings for mechanical protection of a
| motor. To operate the equipment beyond thresholds would result
| in reduced lifespan or immediate and permanent damage to the
| equipment. If this is what the customer requires they have to
| specify that to the Engineer so that when the equipment blows
| up the Engineer is not liable.
|
| Diesel generators for hospitals and water pumps for fire
| suppression systems are generally set up with very loose
| settings as it is clearly worse for a patient to die or a
| building to burn down than to destroy a machine, and this
| requirement is in the specifications.
| brudgers wrote:
| _Diesel generators for hospitals and water pumps for fire
| suppression systems_
|
| Those systems also require regular testing by qualified
| personnel. NFPA 25 requires monthly testing of fire pumps and
| annual flow testing. For low rise buildings with inadequate
| municipal water pressure, a water tower might be cheaper and
| easier. NFPA 99 - Standard for health care facilities,
| requires emergency generators to be tested 12 times per year.
| cactus2093 wrote:
| > it's difficult to test this equipment
|
| Can't you just flip the circuit breaker or just pull the plug
| out? Or does a real power outage usually look different to that
| in some way, like a surge followed by a shutoff?
| zzz61831 wrote:
| You can put your equipment on a _voltage relay_ to make
| failure modes as simple as flipping a circuit breaker. It
| will turn off once voltage drops too much and will wait for
| it to stabilize for specified amount of time to turn it on.
| avh02 wrote:
| Iirc (top of my head), some datacenters go off the grid
| regularly at peak (provider) load times and get more
| favorable rates for doing it. I guess it ensures your fuel
| doesn't go stale and all your transfer systems work.
| WalterBright wrote:
| Around here the typical failure pattern is the power goes out
| for a second or two, then comes back on for a few seconds,
| then goes out for good.
| bradstewart wrote:
| It depends. We built and deployed some IoT devices
| (controlling and reporting status of lights, HVAC systems,
| that sort of thing) to a bunch of greenhouses--one of which
| ran on generator power.
|
| The customer was running the generators right at the maximum
| capacity, and we'd see really, really odd things on the power
| lines. Some times a surge like you mention, sometimes changes
| to the frequency, sometimes changes to the voltage. We
| discovered all sorts of weird brownout conditions in our
| devices.
| jcrawfordor wrote:
| It's difficult in practice to transfer load to generators for
| test especially if there's load shedding involved as is
| common in larger facilities (higher-power-consumption items
| like part of air conditioning capacity are cut off when
| transferred to generators). To help address this a lot of
| more critical facilities are equipped with a test load
| (really just a very large outdoor resistor with active
| cooling) that allows for running the generators at rated load
| for test and exercise without actually transferring. Of
| course, these tests do not always detect problems with the
| transfer equipment, and if things aren't designed and
| maintained well the generator may experience load under real
| conditions that behaves differently from the test load.
| copperx wrote:
| > But it's difficult to test this equipment
|
| You could just, you know, pull the plug and see what happens?
| eigenvector wrote:
| I work in the power generation industry. We have a lot of
| primary/secondary as well primary/standby systems.
|
| The cardinal rule is - test everything. Test it when you
| install and commission it, test it when part of the system
| changes, test it periodically during maintenance shutdowns,
| test it when you have a convenient time to do so without losing
| production (such as an outage to a different system that
| necessitates your system being offline).
|
| Test components individually - at the factory and in the field
| - and test systems end-to-end.
|
| Test with the most adverse possible conditions, not the most
| optimal. Test beyond your normal operating envelope.
|
| When I participate in design reviews as a maintenance engineer
| my primary line of inquiry is: how will I test this stuff
| during operations? Has it been designed in a way that makes
| testing impossible without an expensive outage? Can workers
| safely gain access to components that need routine testing
| without having to de-energize other, unrelated parts of the
| system?
|
| Now not every industry has the budget available to test to the
| extent that we do. But even in our industry, I often see a
| penny-wise, pound-foolish approach of "assume this thing works
| perfectly from the factory then act surprised years later when
| an abnormal condition occurs and it fails".
|
| If something was not tested, it may not work. It might be for a
| very simple reason (like mis-configuration of a single setting
| during installation) or a very complex reason. But either way,
| wouldn't the company rather know their equipment doesn't work
| -before- putting it into service than after?
| a1369209993 wrote:
| Apropos of this, in TFA's case they apparently never tested
| "rip the battery out while the system is running". (There are
| other, harder-to-test ways for a battery to fail, but that
| seems like a obvious and easily-tested failure mode.)
| laurent92 wrote:
| How do you test diesel generators which back up a nuclear
| reactor? I understand you do it during the plant downtime,
| but don't you require something at the other end of the
| network that consumes the 1GW you generate?
| jcrawfordor wrote:
| Some military equipment, especially naval, has something called
| a "battleshort" where electrical protections can be disabled
| during combat, where losing equipment could be more dangerous
| than electrical hazards. It's interesting to think about
| whether this could be applied to DC environments, but honestly,
| I think few DCs actually have this kind of risk aversion for
| downtime. Alternatives like precautionary replacement of
| generators that have been oversped probably come at too high of
| a cost, not to mention that many of those false-positive-prone
| protective devices are there to reduce risk of fire.
| btown wrote:
| https://en.wikipedia.org/wiki/Battleshort
|
| > According to Allied Ordnance Publication AOP-38-3,[1] a
| NATO publication, a battleshort is "The capability to bypass
| certain safety features in a system to ensure completion of
| the mission without interruption due to the safety feature."
| It also says, "Examples of bypassed safety features are
| circuit overload protection, and protection against
| overheating".
|
| > For example, the electrical drives to elevate and traverse
| the guns of a combat warship may have "battleshort" fuses,
| which are simply copper bars of the correct size to fit the
| fuse holders, as failure to return fire in a combat situation
| is a greater threat to the ship and crew than damaging or
| overheating the electrical motors.
|
| > Battleshorts have been used in some non-combat situations
| as well, including the Firing Room/Mission Control spaces at
| NASA during the manned Apollo missions -- specifically the
| Moon landings.
|
| As a side note, with great apology to those who may have lost
| their lives due to the consequences of real-world
| battleshorts - this is actually a really interesting analogy
| for the "war room" scenarios we find ourselves in at
| startups. Risking damage to morale and productivity can be
| acceptable if the alternative is irrecoverable loss of the
| startup's reputation. But this also can't be a sustained
| state of affairs - these types of procedures are meant for a
| battle, and risk compounds if you don't return to a steady
| state. Perhaps adding "battleshort" to our lexicon would make
| it clear that "doing things that don't scale" is often
| necessary but not without its costs.
| helldritch wrote:
| This is one of those comments I so rarely see where what I
| already know is put in to words I've never been able to
| find.
|
| Thank you for this, I'll be updating our documentation to
| include these concepts first thing tomorrow.
| captn3m0 wrote:
| Also on aircrafts:
| https://en.wikipedia.org/wiki/War_emergency_power
| Unklejoe wrote:
| We use something similar on turbocharged drag (grudge)
| racing cars.
|
| The boost controller has a "scramble" button which
| overrides the preset boost targets and allows you to run a
| higher (and unsafe) boost level as long as the button is
| pressed.
|
| This is useful when you're in the middle of a $10,000 race
| and you're losing by a few feet.
| segfaultbuserr wrote:
| What, this is real?! I already thought it was a Hollywood
| movie plot.
| irontinkerer wrote:
| " the P-51H Mustang was rated at 1,380 hp, but WEP would
| deliver up to 2,218 hp"
|
| Wow!
| linsomniac wrote:
| Indeed. I forget where I read it, but it provides that
| power increase for (IIRC) some small double digits number
| of seconds before you need to throttle back, or the
| engine eats itself. If you are able to make it back to
| base, and that WEP wire is broken, the engine needs a
| rebuild before it flies again. Definitely an impressive
| power boost though.
| nine_k wrote:
| Most of military equipment is built to be able to operate
| outside the safety bounds, because the enemy in a battle is
| actively trying to push it outside these safety bounds and
| outright destroy it. Burning down your afterburner chamber
| and winning a fight is better that preserving it and losing
| the whole aircraft.
|
| In a datacenter though your bets are usually much lower.
| Nobody is going to die, or lose many millions, if some of
| your equipment shuts down to prevent it from being damaged,
| catching a fire, etc.
|
| There _are_ though high-stake situations where you want
| exactly that: spend the entire amount of the resources of
| certain hardware to prevent a loss of life, or of untold
| millions, when you are powering a surgery chamber, or a large
| stock trading operation.
|
| People who _realize_ that do over-provision and pay top
| dollar for that when they can afford that. I remember that
| when a major fire occurred in one of the skyscrapers in the
| financial district of NYC, traders of a particular financial
| company were evacuated with their laptops into helicopters on
| the roof, and ferried to a spare office across Hudson river,
| in NJ. To minimize the impact of that, they connected to the
| corporate network via their phones as hotspots, and kept
| trading while airborne.
|
| Of course one cannot hope to pull such an operation off
| without extensive preparation and likely regular drills.
|
| Not preparing to a black swan event during a high-stakes
| event, like translation of a Superbowl match, sounds like
| either not having enough paranoia which is professionally
| required, or, more likely, as a cost-cutting after a wrong
| assessment of risks.
| wvh wrote:
| Many years back I had the opportunity to visit one of those
| data centres at the heart of Europe's financial operations.
| In case of fire, you had a minute or so to get out, because
| then the place is pumped full of argon. I guess that's a DC
| variation of your "battleshort"...
| frabert wrote:
| Interesting, one of the guys that worked on my Uni's DC
| told us that the fire suppressor system is interlocked: to
| enter the DC, you need to open a door using a key. Upon
| opening the door, the fire extinguishing system is
| disabled, and is only enabled when the door is closed. The
| people working in the DC are supposed to keep the key on
| themselves. Also, they used Halon 1301 instead of Argon as
| the gas.
| mark-r wrote:
| Halon is a CFC and isn't legal anymore due to
| international agreements.
| frabert wrote:
| I must have confused it with some other fire suppression
| system I heard of, then!
| mark-r wrote:
| Oh Halon was very popular for a long time. I don't know
| how long they could be grandfathered, but recharge
| supplies must be impossible to get by now.
| dividedbyzero wrote:
| What would they do in case of injured/incapacitated people
| in there? Seems conceivable that some things that could
| start a fire might cause that as well.
| brewdad wrote:
| Name a server rack after those who gave the ultimate
| sacrifice.
| robaato wrote:
| Worked on a project in late 80s for an Italian bank. We
| implemented a SWIFT (financial) interface (on Stratus for
| reliability reasons). A few fun and games:
|
| - The Stratus supposedly had fault tolerant duplexing of
| boards - pull one out and the other keeps working. A famous
| demo where local consultant pulls out the only board which
| wasn't duplicated!
|
| - The machine room was also fire proofed with Halon gas (if
| I recall correctly), but due to security concerns the door
| was locked from inside by operators when present (luckily
| as programmers we weren't expected to work inside with
| doors locked!). Luckily also, it was my first exposure to
| "paired programming"/"paired operating" as in there were
| invariably 2 of them.
|
| - A couple of the operators became too interested in how to
| work things, and wrote a quite comprehensive manual. They
| were "moved on" within the bank, because for security,
| management only wanted "people who could follow
| instructions", not "who can think for themselves".
|
| - the whole headquarters building was in a guarded
| compound, where ultimate protection against "red brigade
| terrorists" (https://en.wikipedia.org/wiki/Red_Brigades)
| were the armed guards. We used to meet them in the ground
| floor cafe every mid-morning, with a revolver on their hip,
| while they drank an espresso with brandy chaser. Really
| inspired confidence that they would be there to protect us
| should the need arise!
| reaperducer wrote:
| _I live in a place where blackouts are very infrequent (perhaps a
| couple per year)_
|
| Ouch. Does anyone know where the author lives that a couple of
| times a year is considered "infrequent?"
|
| Decades ago I lived in a rural area of America where we'd have
| power outages two or three times a year because of storms. But
| I've lived in more than a dozen cities since then, and the power
| has only gone out twice. Once about a decade ago during a
| tornado, and then again last year when the power company replaced
| a transformer across the street.
|
| I ask because it's my impression that electric service has gotten
| much more reliable over the years. There are still access issues
| where I live now (believe it or not, thousands of Americans don't
| have access to the electric grid at home), but reliability seems
| improved. Am I living in a bubble when it comes to electricity?
| deepspace wrote:
| Canada here, metropolitan area. Power outages happen about once
| a decade, usually as a result of a wind storm. I have had zero
| server downtime due to power outages, but UPS / battery
| failures occur at about 4x the outage rate.
| unix_fan wrote:
| I live in dominican republic, and power outages a few times a
| week are common.
| formerly_proven wrote:
| I've had at least a hundred times more power outages due to
| protection devices tripping (usually true positives) than the
| grid going down, so spending 20 minutes to figure out which
| socket would be the best choice to hook all the communications
| stuff up to is a much better investment than buying an UPS.
| FWIW, I had more downtime with the UPS than through actual grid
| outages because the UPS didn't like a battery hotswap and
| powered off, or because the batteries started to gas off
| hydrogen sulfide, which required disconnecting them
| immediately, but the UPS then powered down (without a battery)
| and couldn't start without one, either, so it required rewiring
| a little bit to get going again.
|
| Edit: My UPS is a line-interactive rack-mount APC unit, which
| as I understand things don't actually contain a power supply,
| so everything runs from the battery voltage and is supported by
| the charger in mains operation, but without a battery inserted
| the charger doesn't work, because its control circuit is
| powered by the battery.
| croutonwagon wrote:
| I live in florida. And in an area where most power is overhead.
|
| Storms during the rainy season usually means i experience cuts.
| Usually 1-2 times a month for 3-8 hours ea from May-Nov
|
| Hurricanes are usually expected to be 3+ days at minimum of
| outage. Most recent ones were closer to 14 days.
|
| I have a couple gennys, and interlock kits with 30a hookups on
| my house during these times. I can run 1 genny on the whole
| house, or even 2 since i have a sub-panel with another
| interlock kit.
|
| The only thing i CANT run is my AC. But we have 2-3 window
| units/portables to get by.
|
| FWIW running generators for days at a time is NOT cheap. on my
| setup its about 20-30 bucks a day in fuel alone.
| lostmsu wrote:
| Why not just go solar? Florida seems like a perfect place for
| that.
| [deleted]
| croutonwagon wrote:
| Cost. Not worth it.
|
| Even with my roof (which is east/west facing) the cost to
| just install panels would be 20-30k. And my city has a 1:1
| buy back...And even assuming i sell them back power it
| would take a decade to recoup the costs...and by then the
| panels would be less efficient. And this is with buying 95%
| panels.
|
| but then during an outage....
|
| So you need something to store it... Short of rednecking a
| series of deep cycle batteries the Tesla Powerwalls are
| really the only big option.
|
| And those arent cheap either. To run my house for 2-3 days
| would be in another 10-30k
|
| I can do all of that with 2x7kw gennys and some
| ancillaries. With a 14-17kw i could probably run my AC
| (which have hard start caps on them) Even at 30 bucks a day
| in gas im still well south of even 10k.
|
| Next step up would probably be a active standby generator
| with transfer switch and giant Propane tank to fuel it.
| That would be about 10-15k once permitting and all is done.
| And that adds complexity and cost. But it would mean i dont
| have to manually flip breakers and cutover. (as it is, my
| computers are just set to talk to a NUT server, and
| shutdown in the event i dont cutover within 10 minutes.)
|
| And during storms supply chains are strained. Its hard to
| source diesel and LP and sometimes even petrol (in fact i
| warned a previous company of this, and we almost had to
| shutdown due to fuel levels). And you have to maintain a
| contract with LP providers and usually rent a tank from
| them.
|
| With petrol and my little standby units i can source it
| myself (3-4 am is the best time during runs on gas), even
| siphon from one of our cars.
|
| I may spring for a full kit standby one day. But for me, it
| costs about 2k in generators. Another 1k to have an
| electrician install the interlock kits. And i can
| service/manage the gennys myself. swap them out while i do
| maintenance during extended runs etc.
| 24gttghh wrote:
| What is a 95% panel? Solar cell efficiency is generally
| in the 20-30% range.
|
| https://en.wikipedia.org/wiki/Solar_cell_efficiency#/medi
| a/F...
| Tostino wrote:
| I believe GP was talking about "95% offset" rather than
| 95% efficiency.
|
| So he sized the number of panels to offset 95% of his
| usage is my guess.
| [deleted]
| dervjd wrote:
| _| FWIW running generators for days at a time is NOT cheap.
| on my setup its about 20-30 bucks a day in fuel alone._
|
| What type/size of generator are you running? Might be worth
| taking a look at an inverter unit next time; they're _much_
| quieter and sip gas. Can 't stress the quiet part enough -
| you can hold a conversation a few feet away easily.
|
| Assuming you need 240v since you mentioned you have an
| interlock kit; Champion makes a 5,000 watt model for $1K.
| Will go for 12+ hours on 4 gallons of gas at 25% load. https:
| //www.electricgeneratorsdirect.com/Champion-100519-Por...
|
| If you can get by with a single 5-8K BTU window unit, a WEN
| 56200i/Harbor Freight Predator 2000 (I own one) will last for
| 8-10 hours on a single gallon, keeping both the window AC and
| kitchen fridge running. They're a clone of the Honda
| EU2000i/Yamaha EF2000is, and I've found it to be just as
| reliable. https://wenproducts.com/products/wen-2000-watt-
| inverter-gene... & https://www.harborfreight.com/2000-watt-
| super-quiet-inverter...
| watersb wrote:
| Lived in Florida for about two years. We'd lose power due to
| the neighborhood transformer exploding a couple of times a
| year. That must have gotten expensive real quick.
|
| The quality of the residential wiring in the original half of
| the house was not friendly to my hard disks. I lost four in
| rapid succession. Got a newer UPS, line interactive, had
| better luck after that until we moved out of state.
|
| (That month of disk meltdown made me love ZFS. Didn't lose
| any data.)
| searchableguy wrote:
| Few times a week in summer and twice or so weekly in winters
| here (India). It's not that uncommon in developing countries to
| have outages. Many of them are also arbitrary (not related to
| infrastructure failure) but saving cost, political reasons,
| social events, etc.
| iforgotpassword wrote:
| Germany here. I'd say from personal experience maybe once
| decade. That includes living in a village of ~3000 for eight
| years. One time I remember was caused by an excavator where it
| lasted several hours, the other instances were rather short.
|
| I guess not having earthquakes, floods or hurricanes helps.
| mlindner wrote:
| The other items at least in the US midwest would be ice
| storms (ice coating power lines making them heavy and
| branches getting too coated and falling on power lines) and
| thunderstorms (50+ mph wind coming through bringing down tree
| branches on to powerlines) or lightning strikes hitting power
| transformers.
| InvaderFizz wrote:
| It is highly variable depending on the location. I know of two
| electrical grids in the Bible Belt, less than 10 miles apart.
| One has a power outage every year or two. The other, 10x or
| more per year is not uncommon.
|
| I've lived in many different states and cities, and "it varies"
| is about the best you can say. Areas I would expect to be
| relatively problem free, end up being some of the worst
| offenders (looking at you, El Paso County, Colorado).
| reaperducer wrote:
| I guess I'm just lucky. Thanks for the clarification.
| GloriousKoji wrote:
| A couple times per years sounds about right for California.
| kn0where wrote:
| I have a UPS mostly because my laser printer sometimes trips
| the stupid arc fault circuit breaker[0] that gets false alarms
| incredibly easily. Since my apartment is new construction it
| has AFCI on every circuit. The TV also used to trip it and
| maintenance replaced that circuit's breaker and it's stopped,
| and I'd probably get the other replaced too if not for COVID
| requiring all our maintenance requests to be emergency-only.
|
| [0] https://en.m.wikipedia.org/wiki/Arc-
| fault_circuit_interrupte...
| thewebcount wrote:
| When our office was in Santa Monica, we'd get short (10 second
| - 2 minute) power outages several times per year (5-10 times),
| and real 1/2 day long outages about once or twice per year.
| Several days we were told to go work from home instead.
| dervjd wrote:
| _| Am I living in a bubble when it comes to electricity?_
|
| Your electricity service may not be as reliable as you think -
| some utility power can be quite "dirty" with high levels of
| distortion. There's a lot of infrastructure between you and the
| power company that can cause problems. A good UPS will not only
| protect against outages, but will filter/condition utility
| power.
|
| I live in Chicago, in an older apartment building. I haven't
| had a full on outage in the past few years, but during major
| storms I have seen some flickering and other issues. I just
| looked at the readout on the UPS, and so far it's kicked in 5
| times this year. I have a pretty sizable NAS (40TB) and a beefy
| workstation - the $200 I spent on an APC BR1500MS is well worth
| the protection.
|
| Safety is another consideration. My parents live on their hobby
| farm a few hours away - they are the only house at the end of a
| mile long road with older power lines. I put a similar UPS to
| keep their alarm/phone/network online. If there's a medical
| alarm, fire, carbon monoxide, water leak, etc the alarm can
| still alert the monitoring company, their internet/VoIP
| landline can fail over to cellular, and we can get alerted that
| something is up. Again, the peace of mind alone is well worth
| the $200 (plus $100 for a battery every few years).
| dervjd wrote:
| Forgot to add, I was living in Virginia during the June 2012
| derecho blew through during a period of 100 degree weather (h
| ttps://en.wikipedia.org/wiki/June_2012_North_American_derec..
| .). I was without power for an entire week - even in a nice
| subdivision with buried power lines, in a city of 100K+
| people. UPS won't help for that, but it did automatically
| shut down the NAS and kept my modem/wireless router going for
| a few hours. Bought a 2,000 watt inverter generator for a few
| hundred dollars. If you have somewhere to store it, highly
| recommend purchasing one. Extremely quiet (~50db), sips gas
| (1 gallon/12 hours), and enough power to keep a fridge, small
| window AC, and lights going. Even managed to run the
| dishwasher. https://wenproducts.com/collections/inverter-
| generators/prod....
| laurencerowe wrote:
| Here in San Francisco's Mission district the power used to go
| out every time it rained heavily (2-3 times a year for a period
| of 5 years or so.) Seems to have been fixed a year or so back.
| Heavy rain in SF isn't even all that heavy, though the roads do
| become almost impassable since they're not built with a
| gradient.
|
| In other cities I've lived in power cuts were a once every two
| or three years thing and you could still drive on the roads
| when it rained.
| ChrisMarshallNY wrote:
| I live in NY. We just got our power back after a three-day
| outage. We get short (a minute or two) outages a couple of
| times a year, at least.
|
| PSEG...has their work cut out for them.
| sgt wrote:
| Wait... what? Tell us more about this 3 day outage in NYC?
| bonestamp2 wrote:
| Agreed, compared to most developed countries, a couple
| times/year would be extremely high. But, it's not relatively
| high for America. I remember living in the midwest and every
| major storm usually resulted in power lost to somebody. Many of
| my neighbors had (Generac) generators that would kick in
| automatically when the power went out. They're so common there
| that home depot stocks them on the floor.
|
| In Southern California, we rarely get rain, let alone major
| storms and we still lose power 1-2 times/year.
|
| On the other hand, I lived in a number of areas across Canada
| and power outages were quite rare despite the harsher climate.
| sysadmindotfail wrote:
| My power goes out all the time in Denver. In the summer, with
| no adverse weather. The grid here is a joke compared to most of
| Florida which is FAR more resilient.
| AdrianB1 wrote:
| I have power failures a few times a week up to a few hours each
| time, living in a capital city of an European Union country.
| Having power failures a couple of times per year is "extremely
| infrequent".
| WesolyKubeczek wrote:
| If a power outage is long enough for the battery to go flat, I
| need to power on things gradually, or my UPS will act as if
| overloaded. The stuff I've plugged in barely amounts to 280W.
| It's a home lab, so no much harm done, but also, so much for
| unattended recovery from failure.
|
| It's good for brief outages caused by thunderstorms, though, so
| still better than nothing.
| AnonHP wrote:
| One of the annoying things I've seen with the Back-UPS range from
| APC is that they all seem to have an audible alarm when it's
| running on battery that cannot be turned off. The UPS will beep
| periodically until you either turn the UPS off or until mains
| power returns. This is so annoying that you can find instructions
| and videos online on how to perform a surgery on the UPS to
| disconnect the buzzer from the rest of the circuitry.
|
| Maybe APC really wants to drive users of its lower tier (and
| cheaper) UPSes mad with the beeps and force them to buy the more
| expensive Smart-UPS range that comes with a built-in option to
| turn off audible alarms.
|
| Well, audible alarms do have a place in such systems to inform
| the person that the connected devices or systems are running on a
| limited battery capacity. But forcing that at all times is a big
| annoyance.
| rsync wrote:
| "But forcing that at all times is a big annoyance."
|
| Agreed. The cyberpower devices do let you "silence" the alarm,
| but even with the alarm "silenced" the UPS will begin rapid
| beeping as the battery nears depletion.
| somehnguy wrote:
| During an extended power outage years ago I used my Back-UPS to
| keep my phone charged while I watched Netflix over cellular. I
| ended up wrapping the thing in a whole bunch of blankets and
| towels to muffle the obnoxious beeping. Huge oversight that
| there isn't any button to silence the alarm, there are plenty
| of reasons someone would want to do it.
|
| I meant to tear it apart and remove the beeper after that but
| never got around to it before the battery made it useless
| anyway. TBF it was a few years old at that point so the battery
| giving up wasn't unexpected.
| moduspol wrote:
| I just replaced my old APC Back-UPS with a new one. It lets you
| silence the alarm with a button press.
|
| https://www.amazon.com/gp/product/B01FWAZEIU/
|
| The beeping didn't really bother me but it does frighten one of
| my dogs.
| neilv wrote:
| The article correctly and importantly points out that there are
| many types of UPS. Most recently, I got a production-grade APC
| SMX1500RM2U for home.
|
| Another thing to be aware of, if your PC has a PFC power supply,
| is that it might reboot or have undefined behavior on event of
| the switchover to battery, unless the UPS is designed to avoid
| this.
| jlgaddis wrote:
| PSA: When it comes time to replace your APC UPS batteries, check
| if you have a "Batteries Plus" (or similar) franchise in your
| area (in the U.S., at least).
|
| You can purchase replacement batteries from them for roughly half
| the price!
| Bayart wrote:
| You can get those 7.2Ah batteries pretty much anywhere,
| including Amazon. Just make sure you pick those with the right
| kind of tabs.
| AdrianB1 wrote:
| In Europe, I buy the batteries from the factory and they ask
| for the old batteries in return; this way the price is lower
| and I have no problems recycling the old batteries, they are
| shipped to the factory (a few hundreds km away), dismantled for
| parts (lead, mostly) and used to build new ones.
| lini wrote:
| The explanation of the failure was very strange to me. I know
| there are three main UPS types - offline, line interactive, and
| online. Offline types have the battery disconnected until there
| is a power outage and only use it when needed. Line interactive
| and online use the battery more often to absorb power spikes,
| brownouts, and other anomalies. These two types also use the
| battery more and need replacements more often than offline UPS.
|
| I have been using the same offline UPS and battery for the last 7
| years and it is still working fine - a few days ago it handled a
| 15 min power outage with 50% of the battery.
|
| Can someone explain why offline UPS can fail if the battery dies?
| Is it by design or a manufacturer specific issue (e.g. only APC
| brand ones do this)?
| kop316 wrote:
| Re-reading I was thinking the same thing. Batteries don't just
| "die", they degrade in performance.
|
| How did he also know power didn't go out too? That confused me
| as well.
| danilocesar wrote:
| because he gets emails from the unit when it happens.
|
| I had a script in a raspberry pooling my UPS each minute
| asking if the unit was running on AC or battery, and dropping
| that info into a file when it changed. I know the
| software/daemon can also do something like that.
| jaywalk wrote:
| Yes, but in this case he wouldn't have gotten an email
| since the UPS failed right when the power went out.
|
| I actually had the exact same thing happen to me a few
| months ago. A power flicker so brief that it didn't even
| reset any of my clocks, but it caused one of my cheapo
| standby UPSes to give out.
| monoideism wrote:
| Probably he knew because none of his other electrical
| appliances were reset.
| croutonwagon wrote:
| Theres a few more types than that. But thats the gist of it.
|
| "online" is generally a double conversion UPS.
|
| These are generally the best for clean power to the
| electronics. Since its always supplied by the battery. Its also
| often one of the hardest on the battery.
|
| Line-interactive are probably most common. They are pretty
| solid, but since there is a delay for the cutover, surges and
| really dirty spikes can make it through to the equipment. So
| say a lightning strike or REALLY bad surge on an overloaded
| generator can get through, whereas on a Double conversion it
| may just trip the fuse or breaker. Also running a whole home or
| standby generator on these line interactive can make them trip
| constantly since the generators often dont
|
| A) run at 60Hz (ie: mine runs closer to 63Hz)
|
| B) run with a pure sine wave
|
| You can get inverter generators to help with this. But thats a
| cost too. And otherwise the solution is to "de-tune" the UPS
| sensitivity.
|
| I de-tune this on mine. Its been fine, running on gennys during
| the rainy months for hours and every know and then...days at a
| time.
|
| I have had to swap out power supplies more often..But even
| then, usually thats after like...5+ years of runtime.
| doctorhandshake wrote:
| I was just pricing a UPS for home office use this week as we
| have frequent outages where I am but became a little stuck
| when I realized that to get a UPS that won't barf when my
| generators come online moments after an outage, I'd need a
| double-conversion UPS, which is $$$$. A little stuck for a
| reasonable home office option given this wrinkle.
| knorker wrote:
| Yeah "home quality" UPSs I've found cause more outages than they
| prevent.
| gsich wrote:
| APC deliberately designs their battery case so that the battery
| will die.
| dstaley wrote:
| After reading this, I checked what topology my UPS is using and
| was happy to see it's line interactive. I have two CyberPower
| CP1500PFCLCD units, and am approaching the one year mark. It
| looks like the batteries are even hot-swappable, which I'm sure
| will come in handy when replacing them.
| rcarmo wrote:
| My APC 950VA also died on me unexpectedly, although I suspect a
| power surge: https://taoofmac.com/space/blog/2020/08/02/1800
|
| But the main point in the article is worthy: UPS manufacturers
| have been skimping somewhat on functionality, features and
| quality over the past few years...
| AdrianB1 wrote:
| No, the article is wrong: the low end UPS devices are bad on
| quality and functionality and lead-acid batteries in UPS
| devices is a lot shorter than some people would expect.
|
| I still have a few APC Smart UPS's bought in 1999-2000 running
| in my house; at the same time I had a few cheapies that broke
| after a few years, sometimes in spectacular ways (electronic
| exploded melting part of the battery case); I will not name
| brands, it is not worth.
|
| Since 2000 I changed cases full of batteries, usually every 2-3
| years. The good thing with the APC Smart series is that it
| works even if it gives an alert that the battery is bad, but
| you will get a few minutes of power instead of 30-60 minutes
| (my server & NAS is very low power, 5% of the UPS capacity). I
| also set the server to shutdown when the battery is reaching
| 50%, so I never deplete the batteries. At the same time, the
| UPS on the water pump is usually running on batteries as much
| as it can, so I need to change these batteries after 2 years. I
| have both the server and the water pump in the basement, the
| temperature is around 16-20 degrees Celsius (winter-summer),
| when I was keeping the server and the UPS in the house the
| battery life was at half (~18 months). The heat and the deep
| discharge cycles are effectively killing batteries.
|
| I had the same type of battery on my motorcycles, one lived
| about 8 years and a second one 6 years, but in very different
| conditions: it was warmer, but almost no discharges.
| zzz61831 wrote:
| Deep discharge is a factor, but not a big one, heat has very
| little effect, it only affects voltages at which battery will
| be considered overcharged or deeply discharged as specs are
| usually all for room temperature.
|
| I've used UPSes that discharge batteries no lower than 10.5
| (no deep discharge) and only once in a couple of years and
| that charge them to and keep them at 13.6 volts under stable
| room temperature all year. All batteries lost most of the
| capacity after 3 years, two almost all of it, one had like
| 40% left. In five years only that one was still surviving
| short minutes outages, while initially was able to do a few
| hours. For comparison, I had one battery just laying around
| for 6 years in the same room without touching it and it lost
| only like 30%.
| _rs wrote:
| As far as power surges go, I always put a ZeroSurge in front of
| my UPSes - they have saved the day more times than I can count.
| popotamonga wrote:
| Worst part about UPS that i didn't know was:
|
| The constant humming (no fan, just electrical) so cant sleep in
| same room
|
| The loud can't turn it off beeps when power is out.
|
| And none of those come in the product description.
| robbyt wrote:
| The hum is caused by cheap or warn lamination on the
| transformer. I recently "fixed" an older APC by opening it,
| removing the large transformer, coating the fins in nail
| polish, and adding rubber washers to the mounting screws.
| jlgaddis wrote:
| > _The loud can 't turn it off beeps when power is out._
|
| That depends on the UPS, it seems.
|
| I have a pair of Back-UPS 1500s with the external battery
| packs. They have a button on the front-panel for
| disabling/enabling the audible alarm (just hold it down for 2s,
| IIRC).
| wtracy wrote:
| You can silence the alarm by pulling the battery connection.
| Obviously, that's inconvenient if you want the UPS to be useful
| again as soon as the power comes back.
|
| I personally like the white noise from electronics, so I can't
| help you there.
| SyneRyder wrote:
| There is a way to turn off the beeps on the APC UPS line (at
| least the ES 700 I have), but it involves installing software
| that comes with it onto a Windows machine, connecting to the
| UPS via USB and changing the settings.
|
| It's enough of a pain to do that rather than configure all 3
| UPS devices in my house, I've only ever gotten around to doing
| it on one.
|
| Can't say I've noticed the electrical hum, except during a
| blackout. But I don't have mine in a bedroom.
| _rs wrote:
| Newer models have a button you can press and hold to toggle
| the alarms without plugging into a computer.
| [deleted]
| quesera wrote:
| When the power goes out on an APC UPS, just press and hold the
| "On" button until it chirps. Alarms are silenced.
|
| Now imagine the sound at the APC factory, when the power goes
| out and thousands of UPSes on the charging racks start beeping
| in sync...! (this is not a hypothetical)
| kcb wrote:
| The cheap UPSs aren't very good and don't work well or at all
| with modern PCs. I've had several of these from Cyberpower that
| haven't let me down. Far more reasonably priced than APCs
| equivalents.
|
| https://www.cyberpowersystems.com/products/ups/pfc-sinewave/
| NelsonMinar wrote:
| Seconding Cyberpower. Even their cheaper ones do better than
| BackUPS and don't fail to pass mains power along if the battery
| fails a check. The PFC Sinewave you linked do some nice power
| conditioning. It's a big help for me when my house switches to
| backup generator.
|
| (Why yes, I live in California, land of multi-day power
| outages. Why do you ask?)
| Terretta wrote:
| I like Cyberpower for home A/V racks, and yes, that PFC
| Sinewave line.
|
| Generally the rack mount models, such as CyberPower
| OR1500PFCRT2U PFC Sinewave UPS System, 1500VA/1050W, 8 Outlets,
| AVR, 2U or CyberPower OR2200PFCRT2U PFC Sinewave UPS System,
| 2000VA/1540W, 8 Outlets, AVR, 2U.
|
| Very happy, and stopped having to replace sensitive flat
| screens in bad power zip codes (trees vs. lines every other
| storm, such as for the last week after Isaias).
| greenshackle2 wrote:
| Same here, I've had no issues with the 1500VA version. It's
| line interactive so _should_ still work if the battery dies,
| but I can 't say that I've tested it.
| csnover wrote:
| I don't know if their newer revisions are any better, but I
| bought a CP1500PFCLCD in 2011. When the battery died from old
| age, it cut power to all of the battery backed receptacles
| until I power cycled the UPS. When the charger failed a few
| years after that, it did the exact same thing.
| jpswade wrote:
| I had this exact same issue with this exact same device. I never
| replaced it.
| gsich wrote:
| Some ideas: https://gitlab.com/esr/upside
|
| http://esr.ibiblio.org/?p=7839
| tmp1aa wrote:
| FYI for the APC Back-UPS "Pro" - the "Pro" model's topology is
| line interactive. (Or at least my Australian 1500 version is, as
| well as the other "Pro" models I checked.)
| EricE wrote:
| I'm not sure line-interactive UPSs will guarantee a change in
| behavior in and of themselves since they are still stand-by UPS's
| but instead of cutting over to battery when in an over or under-
| voltage situation they attempt to correct it first.
|
| For critical loads where I don't want interruption I prefer
| online or double-conversion UPS's. Basically they have two
| inverters instead of one. The load runs off of battery constantly
| on the first inverter, and the second continuously charges the
| batteries. There is no cut over time when there is mains power
| interruption since the loads run from batteries.
|
| But I hadn't considered this dead battery scenario so that's
| another thing to add to the checklist of things to ask about. It
| seems that there should be a bypass mode if there is mains power
| to supply power to the load too all the time.
|
| I've found UPS's to be a mixed blessing - when the power does
| glitch they can save your bacon but the battery maintenance issue
| can cause their own outages. If I lived in Florida with their
| legendary lightning I'd just put up with it but I used to have
| UPSs on everything and these days I have really dropped down
| where I have them since we get maybe an outage a year and
| glitches are equally infrequent too.
| ChrisMarshallNY wrote:
| Made me check my two APCs. They are both Line Interactive.
| dreamcompiler wrote:
| I suggest building your own UPS with strictly DC outputs. Most of
| what you'll be plugging in runs on DC anyway. This does mean
| you'll need to dig into some of your equipment to find the DC
| access point, but on other equipment you'll only need to cut the
| wall wart off the end of the cord.
|
| You can choose your own battery and battery maintenance equipment
| for maximum longevity, and choose your own switched power supply
| with different tap points for different DC voltages.
|
| This is simpler and more reliable than AC line-interactive UPSes
| because synchronizing an inverter with wall-socket power is not
| required. Yes, you need some EE skills to build it, but the end
| result will be far more reliable than a cheap off-the-shelf UPS.
| zzz61831 wrote:
| Yep, and once you start using custom DC UPSes the biggest issue
| will be battery chargers that kill lead-acid batteries. Things
| are better with LiFePO4 these days, but for lead-acid I haven't
| found a solution except for literally hacking a pulse charger
| and battery management on top of arduino.
| dreamcompiler wrote:
| I've had good luck with solar charge controllers for RVs,
| e.g. [0]. You have to drive them with DC of course but
| they're designed to be driven by very poorly-regulated DC
| like that coming from a PV panel. So a cheap AC/DC converter
| (either switched or linear) driving one of these things
| should preserve your batteries. Most of them also provide a
| DC load output which gets automatically switched over to the
| battery if the input DC (or in the case of a UPS, the input
| AC) fails.
|
| [0] https://www.rvweb.net/best-solar-charge-controllers-for-
| rv/
| iagovar wrote:
| If you want a poors man home server just repurpose old laptops. I
| do with a bunch of them and it's fine. I know laptops are not for
| that, but they wouldn't have any other use anyway, and it's like
| a server with an UPS built in.
|
| Most tasks are running scrapers or data wrangling so I don't have
| to keep my desktop running.
|
| I've been doing this for maybe close to two years, and for now it
| works. I wouldn't recommend for VMs though.
|
| Also, your router needs an UPS too but it will be fine with a
| cheap one.
| cbanek wrote:
| Yeah I just repurposed a 2015 MBP as a desktop now that it is
| painfully heavier than my 2018 12" Macbook. I just found out
| that it could do 4K60 through the display port, and as a
| desktop machine it's great.
|
| Then the next level of slipping down the chain is the headless
| server or timelapse photo taker. :)
| vladvasiliu wrote:
| > I wouldn't recommend for VMs though.
|
| Why not? I have a laptop with a 4th gen i5 that has VT-x. I've
| upgraded it to 16 GB RAM and an SSD. For now, it's a Spotify
| connect player but I'm contemplating running a couple VMs on it
| too, like pi-hole and whatnot.
| iagovar wrote:
| Well, but that's not that old. If you have that lying around
| then definitely.
| oarsinsync wrote:
| 4th gen is 2013-2014, so up to 6-7 years old.
|
| Sure, that's still reasonable, but it's not young.
|
| I'm also using similar class hardware for my VM server at
| home. Works well enough for home workloads, and for
| everything else there's the cloud on demand.
| Dylan16807 wrote:
| As long as you don't want any 3.5 inch drives, sure. Otherwise
| you probably still want a way to power those.
| mettamage wrote:
| Haha, I started doing this yesterday. IMO it beats an RPI 4
| [1], which I will repurpose as vpn and wifi extender.
|
| [1] Quite often, I couldn't ssh into the pi for all kinds of
| reasons. With a laptop, I don't have to worry about that.
| drcongo wrote:
| I've been running a 2008 MacBook Pro as a server for 10 years.
| I've replaced the battery once, about 2 years ago, and one of
| the fans about six months ago. Other than that, it's been on
| the whole time.
| dividedbyzero wrote:
| What OS do/did you run on it? Thinking about repurposing an
| old 2011 Mac Mini as a server, it should still be more than
| capable, but since it stopped getting newer macOS versions a
| few years back it wouldn't get security updates, that kinda
| worries me.
| sgt wrote:
| Using a MacBook Pro 2015 model as a server. Works great.
| ashtonkem wrote:
| I run a Raspberry Pi 4b, recently upgraded from a 3b+, and I
| believe that a lot of personal computing could (and maybe
| should) be run on them. They're quiet, energy efficient, and
| you could probably run them on a battery if you needed it.
|
| I wouldn't run VMs on it, but I do run docker on it, and that
| works just fine.
| iagovar wrote:
| But it's ARM and that poses some problems. For example, you
| can't put windows into it, and some of my apps are Windows.
|
| Also, RDP. I still hope for something so smooth in Linux,
| using console meanwhile.
| Tiksi wrote:
| In my experience XDMCP/X11 forwarding works reasonably
| well, as long as your network is fairly quick and reliable.
| ben-schaaf wrote:
| It's not officially supported, but you can get windows to
| run on a Pi 4.
| m463 wrote:
| two things:
|
| 1) I think the pi is not particularly power efficient.
|
| I got this impression from this (old) article:
|
| https://www.bitwizard.nl/wiki/Reducing_power_consumption_of_.
| ..
|
| 2) I think the pi would benefit from a more robust filesytem
| layout such as an overlay filesystem to allow continuous
| writes to /var to go to ramdisk.
|
| Openwrt has a layout like this and it prevents flash from
| being burned out and prevents most problems if power is
| abruptly lost.
| knorker wrote:
| Depends what you mean by power efficient.
|
| Watts per low traffic website it's very efficient. CPU is
| generally not pegged at 100%.
|
| For watts per CPU cycle not as much, I agree. Say it takes
| 10W at full power (I've not measured). That makes it 1/10th
| of a normal CPU. But it's like 30-40 times slower.
| ashtonkem wrote:
| > I think the pi is not particularly power efficient.
|
| While there might be efficiency gains available, RPIs use a
| very small amount of power compared to a laptop. Idling a
| RPI4 uses 2.8 watts[0], which not only rates favorably
| compared to most laptops, but is far below what my charging
| cell phone uses. Maxed out my RPI can only hit 15W, since
| that's the maximum power that my official USB C adapter can
| output.
|
| Now that being said, it does depend on what kind of load
| you're expecting to handle. If you're constantly maxing out
| a RPI, it is probably more energy efficient to purchase a
| larger server than to just keep adding RPIs. But if you're
| staying well below the theoretical max of a RPI, it'll
| consume far less than a used laptop.
|
| > I think the pi would benefit from a more robust filesytem
| layout such as an overlay filesystem to allow continuous
| writes to /var to go to ramdisk.
|
| This is one of the biggest drawbacks of the RPI; microSD
| cards cannot handle a ton of writes without frying. I've
| settled on using log2ram to ensure that logs are only
| periodically flushed from RAM to the SD card, to extend the
| lifespan of my cards.
| sosborn wrote:
| Booting to USB is an option.
| silicon2401 wrote:
| what's uptime like on an Rpi? I want to start working on a
| home website and have an old rpi laying around. But I've read
| that their reliability isn't great since they use SD cards.
| Any advice?
| ezconnect wrote:
| If you are not using the camera, it can run for years.
| atomi wrote:
| My rPi3, running Arch, has an up time of close to 3 years
| on the same SD card. It runs various Docker containers
| including 1 for MiniFlux. It's mostly idle but when I need
| it, it's been reliably there for me. Maybe, I've been
| lucky.
| magicalhippo wrote:
| My Home Assistant is running on a Raspberry Pi 3B+. It has
| been running on the same SD card for two years now, with a
| large sqlite database and with debug logging enabled for
| Z-Wave so a fair amount of writing to the card.
|
| It has only been down when the power has been out, and so
| far no issues with the card. It is however an A1 or A2
| class card (I forget which), so supposedly design with
| applications in mind.
|
| It should also be noted that a lot of issues with the Pi is
| due to poor USB cables / power supplies. I had another Pi
| that kept crashing every few days, until I measured the USB
| "charger" cable I was using for it. Turns out it had a
| resistance of almost exactly 1 Ohm. So if the Pi drew say
| 1A, that would be 1V loss in the cable... After I swapped
| cables it has been rock solid. A key point here is that a
| lot of SD cards do not like losing power while being
| written to. Avoid that and a quality SD card should have a
| long life.
| mxuribe wrote:
| I don't have numbers, stats handy but in my couple of years
| experience with Rpis - both regulars and the smaller Ws -
| the SD cards fail well before the Rpis do.
| kokx wrote:
| What I've done with my RPi 4 is attach an external SSD to
| it and mount it to /home and /var. This reduces writes to
| the SD card dramatically. Lengthening the SD card's life. I
| have serious uptime on it, almost a year (since I got an
| RPi 4 basically). It only shutdown with power failures
| (only one, which was entirely my own fault) and system
| maintenance (OS upgrades and other tinkering).
|
| I've also imaged a version of that SD card, so it would be
| easy to just swap out and probably get things running again
| without much hassle.
|
| I'm sure there are more fancy solutions with overlayfs,
| making the SD card read-only except for upgrades. Though I
| couldn't find a nice resource on it at the time.
| uzakov wrote:
| Are there any particular reasons why you want to host your
| website on your home network on the Pi?
| ashtonkem wrote:
| Very long if you're careful to not write to the SD card too
| much. Mine got turned off mostly when I accidentally
| unplugged it from my desk.
| vmception wrote:
| Traders still seem to be the most gullible when it comes to
| buying unnecessary hardware.
|
| They really think their prosumer workstation is going to give
| them an advantage.
|
| I guess thats one silver lining about Robinhood's
| proliferation, many people know its good enough. Gullible
| traders still misread options settlement UI but seems there is
| a selective evolution at play to make that less common too.
| therein wrote:
| Given how unoptimized frontends for crypto exchanges tend to
| be and how rapidly the trading volume could spike in these
| markets, actually it might make a difference.
| rudiv wrote:
| Been running a 2010 MBP for the last few months hosting
| bitwarden, a samba file share, a DNS server, and a ton of other
| stuff. It's been pretty great so far, so much so that I dug out
| another old laptop and set it up as a pi-hole for a friend.
|
| Have you any suggestions for increasing the amount of storage
| one could address? I can't find any Thunderbolt 2 or FireWire
| enclosures so I'm sadly limited to the two USB3.0 ports. Right
| know my plan is to resort to putting a high-capacity 2.5" hdd
| inside the MBP and adding a usb hdd in addition to the one I
| already have. But that doesn't strike me as ideal for some
| reason.
| Dylan16807 wrote:
| Are you saying you can't use a hub?
|
| USB 3 is fast enough for a hard drive.
| iagovar wrote:
| 2.5 SSD for frequent stuff and USB HDD, you have no more
| options.
| mulmen wrote:
| I was considering this but then I stumbled across some ~7 year
| old micro towers. Those little thin client boxes that were
| popular for a short time as a thing that can connect a
| keyboard, mouse and monitor to a corporate network.
|
| Refurbished with a Windows license (if I ever want to use it)
| was less than a surplus laptop. Power usage seems acceptable
| but I'll compare with a Kill-A-Watt. I have one on the way and
| if it works out I'll grab a few more.
|
| I do like the idea of a surplus laptop cluster, mostly because
| of the built in UPS factor but there's a lot of wasted hardware
| there, such as the monitor and keyboard. But I suppose that's
| kind of a feature too.
|
| I have shower thoughts of some kind of custom bladecenter made
| of old laptops but that's a lot of work for probably zero
| benefit.
| pdimitar wrote:
| To me the main problem would be the noise. I don't have a
| dedicated server room and even if me and my wife's bedroom +
| living room is quite big it'd still be annoying during the
| night. But I am quite fond of the idea to reuse old laptops
| regardless.
|
| Can you post a link to those 7 year old micro towers, please?
| mulmen wrote:
| Yeah noise is why I didn't go with surplus servers, and the
| power requirements. Proper servers are actually pretty
| cheap, less than these tiny towers even. But the power and
| noise is just too much. Plus less horsepower is actually
| more interesting to me so my workloads have a hope of
| hitting scaling limitations.
|
| The tiny tower I have on the way is one of these: https://w
| ww.lenovo.com/us/en/desktops/thinkcentre/m-series-t...
|
| They're available in a bunch of configurations and on
| multiple sites so you can look around for a good deal that
| fits your needs. I found one with an SSD for additional
| power savings.
| pdimitar wrote:
| Thanks a lot, I will.
|
| In regards of power efficiency I'd still be drooling over
| one of the Xeon D-1600 configurations but haven't found
| one that's not in a rack form factor yet.
| 2OEH8eoCRo0 wrote:
| This has served me well for a year ($80 Dell laptop w/ an i5
| from Craigslist) but I did just splurge on a Synology NAS and
| an APC UPS because having multiple external hard drives plugged
| into the laptop was quite dicey. The laptop is still a Plex
| server but now I have peace of mind for the data.
| AdmiralAsshat wrote:
| Just be sure to check on them every once in awhile, lest the
| battery swell go unnoticed.
|
| https://old.reddit.com/r/spicypillows/
| antisthenes wrote:
| That's much less of a problem for laptops whose batteries are
| just 6-8 18650 cells in a plastic enclosure.
| Tiksi wrote:
| Well, used to be. As I understand it newer laptops are more
| and more often using pouch style batteries to keep things
| thinner by using any available space.
| bserge wrote:
| Laptops are incredibly versatile haha. You can take the display
| and keybooard off for a smaller footprint and better cooling,
| too.
|
| Relatively recent smartphones also work great for a lot of
| stuff.
| lsllc wrote:
| Like the author, I rarely see power interruptions that last more
| than a second or two (unless there's a major snowstorm or
| something).
|
| It's kind of annoying and I'd love to see a solution that isn't
| just "get a battery based UPS" -- maybe something capacitor
| based, enough for say 15-30 seconds?
|
| I guess I could get a flywheel [0], but I don't think it'd fit in
| my basement.
|
| [0] https://www.vertiv.com/en-us/products/brands/liebert/?id=59
| NAR8789 wrote:
| You mean something like this?
|
| https://www.atx-upsu.com/
|
| Looks like it's capacitor-based, removes the need for an
| inverter, and even has a clever way of communicating to the
| host, by taking over the power switch connector.
|
| Unfortunately, I can't seem to find a price or where to buy.
| Would love to see more momentum around products like this, and
| marketing directed at home systems.
|
| EDIT: Thought of one more system that uses capacitors to limp
| to a clean shutdown--the Unifi Cloud Key Gen2.
|
| Again though, the power solution isn't packaged for consumer
| use.
|
| Though, maybe it'd be amusing to try to hack together a NAS out
| of Cloud Key Gen2 Pluses... there's a hard drive bay in each
| one ;D
| pacaro wrote:
| Back in the late 90s I had a PC motherboard that had a
| capacitor for exactly this. I could (if i was quick) change
| which outlet the pc was plugged into without loss of uptime
| zantana wrote:
| I also remember a green pc set up which used one of the low
| power x86 clones (Via?) in the 90s which used the bios
| battery double as a mini ups similar to that.
| mprovost wrote:
| At the reasonably sized datacentre that I ran we had a voltage
| conditioner that also had "sag protection". It was an HPC shop
| and we decided that it wasn't worth the money to put the
| compute on UPS (just storage and core servers but the Top 500
| machines ran off mains) but we still had 10s of millions of
| dollars worth of hardware that a lightning strike etc could
| fry.
|
| The conditioner provided a constant voltage to the servers and
| could correct "sags" where the voltage would drop, and it could
| keep things going for a few seconds if the power went off
| completely. As you say this took our total outages down from
| probably 10 a year to maybe 1 or 2 - most outages are quite
| short. Although looking at the graphs on this thing, there were
| pretty frequent surges and sags coming from the street, like
| when you see light bulbs flicker in your house.
|
| One other thing we noticed was that if there was a short
| interruption, all of the HP servers could survive for a second
| but the Dells turned off right away. Different power supplies
| store up some amount of power locally.
|
| https://new.abb.com/ups/power-and-voltage-conditioners/volta...
| hinkley wrote:
| As we were growing, we slowly converted a telco hardware server
| room into a real server room. Knocked out a wall to get enough
| room volume for a mini-split AC, removing the sprinkler head,
| moving the servers... And replaced all the wiring with plugs
| higher on the wall so that flooding wouldn't result in an
| electrical fire.
|
| So when it came time to move our staging database over to the new
| wiring, the head of IT unplugged the UPS from the wall, the UPS
| complains like UPSes are wont to do in such situations, and in
| the time it took him to untangle the cable and plug it into the
| new circuit, the UPS dies. Bad batteries that the health checks
| didn't detect. Unplanned shutdown of our shared database. Whups.
|
| And that is when management was taught about redundant power
| supplies, and periodic UPS maintenance.
| dervjd wrote:
| _|And that is when management was taught about redundant power
| supplies, and periodic UPS maintenance._
|
| And hopefully about setting up monitoring on your UPS to keep
| track of battery health ;)
| hinkley wrote:
| The UPS was reporting as green. Not so much you can do when
| the hardware is lying to you.
| m463 wrote:
| I wonder if the tesla powerwall acts as a UPS.
|
| EDIT: I found an interesting thread about the powerwall,
| switchover and using a UPS:
|
| https://teslamotorsclub.com/tmc/threads/powerwall-2-ups-conn...
|
| it appears the powerwall moves the line frequency up from 60hz to
| as much as 65 hz as a signal to the solar power inverters and
| that can trip up some UPSs which monitor 60hz as an indicator of
| "good power"
| ozim wrote:
| I have a horror story with 700VA APC ES-B700G, I bought it for my
| NAS in case I would be updating its operating system not to have
| it turned off by random power loss.
|
| I had issues with power supply to my apartment once in 2 years or
| something like that.
|
| This model has "controlled by master" outlets which I did not use
| because I needed only backup lines connected to battery. That
| "controlled by master" thing would turn on once in 3 months
| without reason.
|
| Then one day there was no power loss and UPS flipped and turned
| off power to my NAS and to my devices. Battery was good power was
| there but switches flipped and my NAS was turned off without
| warning. There was no system updates, maybe just normal writes to
| the disk.
|
| Turned out my HDD WD-RED 1TB died because of that one flip. It
| would have been better for me not to have a UPS...
| christefano wrote:
| I'm sorry for your loss.
|
| It sounds like you used a Back-UPS unit instead of a Smart-UPS,
| which I've heard switches to battery 10x faster than the Back-
| UPS.
|
| After learning this I won't use a Back-UPS for anything where
| meaningful data loss might happen. They're great for lights,
| cable modems, WiFi routers, etc., though.
| ozim wrote:
| Thanks, it was just a faulty unit that I trusted too much.
|
| I was doing turn off tests with my NAS attached and it was
| switching correctly and NAS was not going down, I had couple
| RPis connected also not going down and notifications from NUT
| were in logs. Where my NAS was NUT server and RPis had NUT
| client.
|
| It was that one day when UPS malfunctioned in a bad time.
| Where my electricity provider was more reliable than UPS I
| owned. So bad risk management on my side.
| colechristensen wrote:
| TL;DR some UPS systems will shut down power when they detect
| battery failure even when mains electricity is working.
| AnIdiotOnTheNet wrote:
| UPSs, in my experience, quite often have or develop faults that
| defeat their purpose. We just threw one out that would cut
| power entirely during self-test, but _only_ during self-test,
| not during an actual outage. I 've seen their battery
| monitoring circuits fail such that they report a battery as
| good until power is cut and then die immediately. The other way
| also happens, reporting all batteries as bad even though they
| might be brand new, so you're never sure when to replace them.
|
| I've come to the conclusion that if you are going to use a UPS,
| your equipment should always be plugged in to at least 2 UPSs,
| either via redundant power supplies or an ATS PDU.
| eigthbits wrote:
| I found this guide by Cyberpower to be a clear and concise
| explanation of the topologies of UPS offered and their benefits.
| Yes it's content marketing, but it's good.
|
| https://www.cyberpowersystems.com/resources/choosing-an-unin...
| russellendicott wrote:
| I recall from my years as a small business sysadmin that some of
| the Smart-UPS systems that have a serial connector for management
| access require a special serial cable. If you plug in a
| "standard" serial cable it cuts power to the whole UPS unit and
| your whole server rack loses power even if the batteries are
| fully charged. That was a bad day.
| jlgaddis wrote:
| Indeed. I, too, learned that lesson the hard way many, many
| years ago! I also know several other folks who learned that the
| same way that you and I did.
|
| Although I'm a bit "old school" and generally prefer serial
| (RS-232) ports, this is one case where the change to USB really
| was a huge improvement!
| quercusa wrote:
| Yep, sometimes there's nothing as loud as silence!
| ramshanker wrote:
| One thing I always wonder about these home server is this. When
| you are leaving house for a long vacation, is it really safe to
| leave some electrical appliances working? Aren't people afraid of
| fire hazard. What if there is a short circuit while you are away.
| A smelling short circuit would definitely burn something if left
| unattended for few days.
|
| For once there was a high voltage fault in my neighbourhood,
| destroying few lights, all mobile chargers plugged in and
| microwave left in standby. Had I not been home, and fault lasting
| more than 5min, things might have gone really bad.
|
| Now on, Whenever I leave my home for long duration, I just empty
| the Refrigerator and switch the house mains supply off before
| loving the house.
| 0xffff2 wrote:
| Before the pandemic I spent ~1/3 of my time away from home
| anyway (work during the week, either out camping or otherwise
| out and about for at least 1 in 3 weekends). I certainly didn't
| unplug everything every time I left for work. I don't really
| see a significant difference in risk profile for a week long
| vacation.
| formerly_proven wrote:
| Electrical fires inside stuff that isn't the cheapest straight-
| from-china import shit are incredibly rare. Most fires causes
| are A) very old wiring that has never been attended to but
| loaded to the max B) people messing with mains wiring and
| causing a fire (e.g. bridging thermal cut off switches in cable
| drums) and the occasional person drilling into a cable in the
| wall and hitting it just-so that PE is untouched but L and N
| are getting just cozy enough to start a fire without tripping
| the line breaker.
| amluto wrote:
| I find it surprising that service panels don't have more
| extensive protection features. I would like my main breaker to
| trip under any of these conditions:
|
| - Sustained overvoltage. Any overvoltage lasting too long to be
| handled by a surge protector should trip the main breaker.
|
| - Sustained undervoltage. Some devices don't like this.
|
| - Phase error. A two phase main should detect incorrect phase-
| to-neutral voltages and incorrect phase-to-phase voltages. A
| three phase main should also detect incorrect phase sequence.
| This should also catch some cases of a disconnected neutral.
|
| - Excessive neutral to ground current. In the US, for reasons I
| personally strongly dislike, every "service" has a connection
| from ground to neutral, usually in the meter box or the main
| panel. Various errors can cause substantial current to flow
| through this connection and can be dangerous. For example, if a
| house and the utility both have excellent grounds but the
| house's neutral feed breaks, all the voltages can be close to
| correct and the house's neutral current will return to the
| utility through ground. This is dangerous and will not be
| detected by common equipment. (A whole-house residual current
| detector would satisfy this, too. I think these are used in
| Europe.)
| xx_alpha_xx wrote:
| we had our house neutral chewed through by mice in the
| electric meter - caused really bad problems :(
| reaperducer wrote:
| _One thing I always wonder about these home server is this.
| When you are leaving house for a long vacation, is it really
| safe to leave some electrical appliances working?_
|
| I used to feel this way, but then I realized that the
| electronic devices don't know I'm away on vacation, or when
| I've returned, and they're just as likely to start a fire when
| I'm down the street getting coffee as on the other side of the
| planet. And when I return, my presence doesn't magically reset
| some catastrophe timer and everything's all better because I
| touched "base."
|
| That said, if I'm gone from home long enough that I turn off
| (or down) the refrigerator, then I'll unplug everything. So I
| guess I'm still a bit paranoid.
| EvanAnderson wrote:
| Short of being home and reacting immediately with a fire
| extinguisher when the smoke alarm is triggered I certainly
| agree with you that there's little that being away changes w/
| respect to the electrical fire risk profile and potential for
| loss. Whether you're gone for a week or gone for 15 minutes
| makes little difference in responding to a fire.
|
| Responding to a water-related disaster is a different story,
| though, and worth bringing up.
|
| You might want to consider turning off your water at the main
| if you're going to be away from home for an extended period.
| I was fortunate in that the only water-related failure I've
| had personally was a ruptured water heater leaking into a
| floor drain of a 1st floor utility room. I know others who
| haven't been so lucky (having clothes washer hoses rupture,
| fixtures fail, etc) and have had water running inside their
| home for an extended period (several days, in one case).
| Until someone notices the local municipality reading
| excessive usage, a neighbor noticing water running out a
| patio door, etc) the damage continues and, to add insult to
| injury, you're also getting charged for the water / sewer
| usage.
| outworlder wrote:
| There are failure conditions that are not immediately
| catastrophic. The reasoning being that if you come home after
| a work day (or even better, after coming back from your
| coffee down the street) and see that a device malfunctioned
| you will attend to it. As opposed to leaving it plugged in
| and turned on for weeks while you are not there.
|
| A lot of devices will smoke before starting a fire, sometimes
| for quite a while until temps increase sufficiently for
| ignition. You would smell the smoke and figure out the
| culprit.
|
| Turning off everything is still worthwhile while you are
| away. This is just risk management. It is a small risk (maybe
| you have faulty appliances or house wiring? maybe you live in
| an earthquake or tornado area? etc) but the mitigation is
| also not very inconvenient.
|
| That said, if you can have a smoke detector pinging you (or a
| similar device - Amazon's cameras have a microphone that can
| alert you to alarms) it would be better. As you point out,
| stuff could happen while you are temporarily outside the
| home.
| Erlich_Bachman wrote:
| Isn't a short circuit going to just blow the relevant fuses?
| Also most UPSes should protect from surges as well as power
| outages.
| stingraycharles wrote:
| I can answer this as I'm currently on a two-week holiday and I
| have a small homelab running at home.
|
| First and foremost: fire alarms. Buy them, and use plenty of
| them.
|
| Secondly: let your neighbors know you're on vacation. This
| implies a certain amount of trust with your neighbors, but it's
| good to be on good terms with them for more reasons than just
| this.
|
| Thirdly: I get notifications if a server goes down or a fire
| alarm is triggered.
|
| With all this in place, I don't worry at all. I may be somewhat
| ignorant or oblivious to certain risks, but in general I trust
| the safety net I just described.
| michaelt wrote:
| _> What if there is a short circuit while you are away._
|
| If you believe fires start at random, there's no difference
| between a 2 week holiday and 9 weeks working 8 hours a day.
| yardie wrote:
| For those unaware of what the different lines do:
|
| Here is how I differentiate the APC brand:
|
| * Back-UPS: inverter offline, expect a 15-20ms power transfer
|
| * Smart-UPS: interactive, inverter is always online 2-5ms
| trasnfter
|
| * Symmetra and above: inverter online, voltage conditioned, 0ms
| transfer
|
| Most desktops will work just fine with the Back-UPS line. The
| processor is practically sleeping. Workstations should be on a
| Smart-UPS because the PSU capacitor won't have the capacity for a
| brownout with a Xeon-class CPU and multiple GPUs.
| dfox wrote:
| Looking at the schematics of some old models of BackUPS I found
| online the output relay needs to be powered in order to supply
| output from mains. Combine this with slightly funky internal
| power topology where +12V for internal logic comes mostly
| directly from the battery and it is pretty clear why battery
| with shorted cell(s) causes the thing to completely shutdown
| (probably even due to thermal shutdown of the LM317 in charging
| circuitry).
| borner791 wrote:
| It's more complicated than that. There are Smart-UPS online.
| Thats double conversion also 0ms transfer
|
| Some of the "newer" online models will have a green mode, which
| although double conversion green mode introduces a transfer
| time (~2ms, basically relay lift time).
|
| Backups are also square wave, or stepped sine Smart are
| Sinewave output.
|
| This is specifically APC.
|
| Also remember there are tare losses (copper / magnetizing and
| conversions), so a UPS just sitting there can use up to 30W.
| quesera wrote:
| Corroborated!
|
| Back-UPS stepped sine wave has about 3 square steps above or
| below zero, so it's a very rough approximation of a sine
| wave. Adequate for many kinds of equipment, but ugly on a
| scope.
|
| There is, or used to be, a pin on the Smart-UPS line that you
| could tie high (or low?), to tell the device to operate in
| "Online" mode (inverter always active, line power
| continuously tending the battery). APC also sold it
| preconfigured that way as a separate, more expensive,
| product. :)
|
| There's also a trick to jump-starting an unplugged-but-
| charged Smart-UPS. I've used this for several hours of remote
| power in inconvenient locations.
|
| Quality devices, but test them regularly. The switch from
| idle to high-draw can be violent, and it takes out weak
| components. Similar to tungsten lightbulb filaments.
| croutonwagon wrote:
| Not always.
|
| I have these.
|
| https://www.apc.com/shop/us/en/products/Power-Saving-Back-UP...
|
| They are line-interactive. Most of their "tower" UPS models
| seem to be Line Interactive.
|
| Its those little ones that look like oversized surge protectors
| that usually are offline.
| yardie wrote:
| I have the next step up from this, the 1500 VA. I assumed the
| UPS under my desk was the Smart-UPS series but I can see it
| is the Back-UPS Pro. I haven't been in the office in months!
| magicalhippo wrote:
| > Workstations should be on a Smart-UPS because the PSU
| capacitor won't have the capacity for a brownout with a Xeon-
| class CPU and multiple GPUs.
|
| Also make sure it's rated for the load. My UPS went "lol nope"
| when I lost power while I was gaming, because I had forgotten
| about it when I went from single mid-range GPU to SLI top-end
| GPU...
| yardie wrote:
| Lots of users have desktops, monitors, chargers, and even
| heaters plugged into our UPSes. To them it's just a chunky
| power strip. They're lucky if they can squeak out more than 5
| minutes on battery.
| magicalhippo wrote:
| Well if I had one minute that would have been plenty. But
| mine went right into "overload" after a second and shut
| itself off.
| jaxx75 wrote:
| I had 3 hard drives (likely) fail because of brownouts
| regularly occurring at a residence when high-amperage devices
| kicked on (power tools, air con, hairdryers, etc). The line
| would drop into the 80-90v range (120vac) which wasn't enough
| to turn anything off, but you could notice the lights
| "flicker." After a voltage conditioning UPS was added, haven't
| had a hdd failure
| jcrawfordor wrote:
| For situations where a UPS is too expensive or impractical
| you can also buy pure voltage regulators that use some kind
| of autotransformer, like the APC Line-R. I worked for an
| institution for a while that had every laser printer on one,
| there had been some bad experiences with losing laser
| printers to overvoltage incidents but they generally draw too
| much current to go on a UPS. I've also seen them used for A/V
| equipment.
| formerly_proven wrote:
| Hold-up time is one of these things (besides long full-load
| life) that separates cream from crop in power supplies. High-
| grade ATX power supplies don't just promise 25+ ms hold up
| time, but actually deliver.
| detaro wrote:
| Some better review outlets test for that, since you can't
| rely on PSUs actually managing the spec-required 17 ms (I
| think that's the number, something in that ballpark)
| j88439h84 wrote:
| Which reviewers do that?
| detaro wrote:
| Two come to mind immediately:
| https://www.tomshardware.com/ does. German magazine c't
| at least did, haven't looked at their reviews recently.
| Qub3d wrote:
| http://www.jonnyguru.com/ Has always done some pretty in-
| depth electrical profiling of PSUs. I usually check them
| when I need to buy one.
| beamatronic wrote:
| I did a lot of research before I bought a UPS. The constant that
| I saw across various brands was that these batteries will die
| after a few years without any warning. They have to be replaced
| proactively. No if's and's or but's.
| firekvz wrote:
| I have 4-5 hours outages every day, I use 2 APC ups to keep my
| modem and router up, while I still work with my laptop.
|
| It works perfectly for me, these APC devices have given me at the
| very least 1500 hours of continuos internet access where I could
| work or entertain myself during the outages over the last 4
| years, so I think the 180$ per unit it cost, was a pretty good
| investment in my case
| zymhan wrote:
| I was very pleasantly surprised when my power went out one day,
| but my UPSes managed to keep the Modem/Router and my PC
| running, and I got to finish my multiplayer game :)
| beervirus wrote:
| That's a crazy level of downtime. Whereabouts?
| bowmessage wrote:
| I'm surprised to see that if the power is out in your area,
| that the power used to boost coax signals in your area is not
| out as well!
| jcrawfordor wrote:
| If the cable provider offers digital voice, they're required
| to have backup power for their infrastructure for at least 24
| hours (or 8 hours under older regs) to allow for 911 calls.
| The power injectors used for cable amplifiers usually just
| have a couple of lead-acid batteries in them.
| hackmiester wrote:
| Just because they are required to do it, doesn't mean they
| do it. My source is experience.
| bonestamp2 wrote:
| Why is there so much interruption to your power?
| watersb wrote:
| I had an APC UPS battery age out on me, after only a couple of
| months after purchase. Back-UPS XS 1500.
|
| I called their customer support, and they asked about the kind of
| equipment I had plugged into it.
|
| My main NAS motherboard had died, and I hadn't gotten around to
| the full rebuild that was going to require. So I had ended up
| with about five or six cheap USB external drives, with those
| "wall wart" DC power supplies, strung along a couple of power
| strips that were plugged into the UPS. That plus a 27-inch iMac.
|
| It was generally not much power - not much surge to spin up, or
| to power up the Mac, and of course at idle was less than 100
| Watts.
|
| APC Customer Support said that the power strips might actually be
| weirding out the battery.
|
| They sent me a replacement battery at no charge, and suggested
| that I go with a Smart-UPS, with their Power Distribution Units
| if I needed more outlets.
|
| I had always thought the rack-mount PDUs were a silly expensive
| replacement for a no-name power strip. But I had long had a keen
| interest in this sort of IT equipment fail, after witnessing some
| spectacular crazy failures in corporate, and losing the
| manuscript while I was writing a book on small-office IT
| practice.
|
| So I bought a basic PDU, and a Smart-UPS rated at something like
| 700 VA.
|
| That has been rock solid. Even better than a larger setup I had
| with some big CyberPower systems.
|
| I'm willing to go along with the cargo-cult of PDUs now. I would
| be quite surprised if there were any significant difference among
| the basic PDUs of well-known brands.
|
| I still have those USB drives. They've lasted about as long as
| the hamsters, not as long as the dogs.
| rsync wrote:
| "APC Customer Support said that the power strips might actually
| be weirding out the battery."
|
| I think it's more likely that you purchased a guerilla-
| remanufactured unit that was properly sealed and packaged to
| look brand new (with hologram stickers and anti-tamper seals,
| etc.) but had an old, already dead battery that was
| reconditioned just enough to last a few cycles after purchase.
|
| Did you buy this directly from APC ?
| watersb wrote:
| I don't recall the vendor but I believe I purchased the
| original Back UPS via Amazon. So, perhaps not quite the best.
|
| I bought the SmartUPS and PDUs from an authorized dealer that
| APC Customer Support referred me to.
|
| That worked out better.
| nippoo wrote:
| Where I live (in the UK) the power is reliable enough (one outage
| every 3-5 years) that I only tend to spec UPSs for devices with
| dual PSUs - one raw mains, one UPS-protected. I've had more UPS
| failures than mains failures in the past decade... and mains
| power will normally come back up, starting the equipment
| automatically, while failed UPSs generally require manual
| intervention to fix, and consequently much greater downtime...
| EvanAnderson wrote:
| My experience has been that inexpensive UPS units create more
| problems than they solve in the long-run. Spending more money up
| front to get a corporate-production-grade unit is worth the
| money.
| olyjohn wrote:
| This exactly. If your power only goes out once or twice a year,
| your crappy UPS is more likely to fail before it proves any
| value.
| dragontamer wrote:
| > While I was away from home on a long work trip, suddenly I
| could no longer connect to my server and I had not received an
| e-mail from the server informing me of any problem. Luckily it
| was near the end of my trip so I was not too inconvenienced. When
| I arrived home I found that the UPS was sounding an alarm and was
| not supplying power to the server even though there was mains
| supply to the UPS. It transpired that the UPS battery had
| suddenly died without warning and could no longer hold a charge,
| and this had happened while there was mains supply to the UPS,
| i.e. there had not been a power cut while I was away. Fortunately
| there was no loss of data on the server; I was able to run fsck
| during boot-up.
|
| And this is why professional servers have two, redundant, power
| supplies.
|
| If you had two power supplies, the UPS would fail, but you'd
| continue to function off of mains voltage.
|
| UPS can fail. Mains can fail. Two power supplies hooked up two
| both powering your server redundantly means you'll only fail if
| both fail simultaneously.
| zzz61831 wrote:
| That's not really a proper way to deal with it. Proper UPS for
| a home server or any standalone server or appliance has to hook
| up either after ATX power supply in parallel and provide all
| the ATX voltages or hook up directly into a power supply to
| save a bit on extra converters. This way UPS failure won't
| affect anything and such UPS will be much more efficient.
|
| It's just that consumer home UPSes are almost scam level
| products designed to profit from naive people. They are both
| not improving things for an average user and killing batteries
| after like a year of operation (lead acid batteries can last
| for like a decade when not subjected to those UPS chargers).
| greenshackle2 wrote:
| My cheapo UPS certainly improved things for me when I lived
| in an apartment where the entire unit minus kitchen
| appliances was wired to a single 15A circuit. I tripped the
| breaker semi-regularly by forgetting to turn off the AC
| before using the vacuum cleaner or toaster oven or whatever.
| mprovost wrote:
| That doesn't protect against surges though - any weirdness from
| the mains power would still fry your server through the
| unprotected power supply.
| dragontamer wrote:
| Surge protectors are pretty cheap, and I generally assume
| that all expensive equipment would use them when connecting
| to mains.
| adrianmonk wrote:
| Also, surge protectors wear out and should be replaced
| before they lose the ability to protect.
|
| This will probably occur at a different time than when the
| UPS wears out, so it could be beneficial to keep them
| separate so you can replace the surge protector only.
| marcosdumay wrote:
| You don't need an UPS to protect against surges. In fact,
| UPSs aren't surge protection devices; they may filter a few
| of those, but they should be protected too.
| bob1029 wrote:
| Over the years I have lost a lot of confidence in UPS units which
| do not use double conversion topology.
|
| I have a fairly expensive line-interactive unit that can be
| tricked into doing bad things just by power cycling my laser
| printer which is plugged into the same circuit (but not the
| actual UPS). One day this caused me more trouble than it was
| worth WRT lost work. I would have been better off plugged
| directly into the grid and just taking the 100 millisecond
| voltage dip at the PC's power supply. This is one area where
| buying high quality PSU can go a long way. High wattage Seasonic
| units can ride through some pretty nasty conditions before
| needing any outside help.
|
| I also have a cheaper passive-standby modified-sinewave unit
| which has never misbehaved in terms of trigger conditions, but it
| is hot, noisy and otherwise does not inspire any confidence when
| it's running on its inverter. I would also never dream of
| plugging anything into this unit that uses a non-switching power
| supply.
|
| Again, I am faced with the reality that you get precisely what
| you pay for. I always assumed double conversion was expensive
| paranoia never for home use, but over time this has proven out
| just like everything else when looking at the value equation of
| technology.
| PaulHoule wrote:
| My own UPS system is focused around keeping the telephone
| system and one DSL modem up and running through 2 days without
| power. That way if there is a bad thunderstorm there is no
| panic about working at home, I can use a laptop and tablets and
| communicate as much as I need.
|
| I have a PC tower server and realized off the bat that it would
| not be feasible to supply it with backup power for any
| worthwhile period of time. If the power goes out it will crash,
| but it runs on ext4 and ZFS and odds are very good it will come
| back when the power does and put itself back together.
| HumblyTossed wrote:
| I don't need days of power, but I wanted a few hours. I ended
| up getting a Belkin Battery Backup REV B, BU3DC001-12V off of
| ebay and modified the barrel connector to fit my cable modem
| and router. I can get at least 3 hours (I haven't tested it
| longer than that). I'll probably get another while they're
| still available.
|
| As for my server, I have it on a UPS big enough to allow it
| to shut down (with some slack for battery degradation).
| That's all I really need.
| ComputerGuru wrote:
| I'm with you on zfs (although it is a pain to restore
| overwritten metadata, that's not a typical symptom of
| power/controller failure) but please change ext4 to jfs or
| xfs. Xfs has a bad rep from the early naughts in terms of fs
| corruption but actually addressed the underlying issues and
| today both those options are equally great.
|
| I've tested all three extensively with unreliable media
| (raspberry pi kernel dev testing on an sd card) and ext4 was
| the absolute worst.
| pdimitar wrote:
| Can you elaborate for which storage mediums ext4 was the
| worst? The microSD cards? Or even normal SSDs?
| LinuxBender wrote:
| I too use double conversion UPS. Liebert Vertiv GXT4 in my
| case. The power in my neighborhood is sloppy and the power
| company refuse to replace the transformer until it goes out
| entirely. The neighbor has a septic pump that creates nasty
| spikes. I've had multiple APC UPS literally catch on fire. It's
| always the tower models with the real time voltage regulators
| that catch on fire. The floor power strip models have been rock
| solid, but they would beep every time the neighbors pump kicked
| on. I tried power conditioners, filters, isolation
| transformers, but in the end, it was the double conversion UPS
| that cleaned everything up and the Liebert has provided
| reliable power ever since. Some day I want to go solar, but I
| would have to move somewhere else first.
| tenebrisalietum wrote:
| > just by power cycling my laser printer which is plugged into
| the same circuit
|
| So I encountered in a previous IT helpdesk job a laser printer
| connected to one of the tower APC units, with a wattage
| display.
|
| Laser printer (it was a Ricoh Aficio SP 4100-something MICR
| printer for checks IIRC) was connected to the battery backup
| set of receptacles for some odd reason.
|
| Any time the laser printer would start up, or run, and I
| presume charge the fuser, it would briefly spike up to 900w and
| often set off an alarm. It was rated for 550w. I think sudden
| high loads like that could be damaging to the unit.
|
| I would not attempt to connect a laser printer to a UPS at all,
| even if not connected to backup battery--IMHO it's in the same
| category as high-current devices like toasters and hair dryers.
| Many commercial copiers I've seen have some type of large surge
| protector but no UPS.
| BuildTheRobots wrote:
| Laser printers plugged into UPS's aren't great (and then
| there was my previous boss who destroyed a pretty large unit
| by repeatedly boiling a kettle from it during a power cut),
| but it's worth pointing out that the OP had his laser plugged
| into the same circuit as the UPS but not onto the battery - I
| took that to mean it's on the same radial/ring/breaker rather
| than connected to the UPS at all.
|
| I'm guessing the surge current to the laser was causing the
| UPS to register a brownout and potentially not behave
| correctly at that point.
| epc wrote:
| Buy an automatic transfer switch. Plug one input into a UPS, plug
| the other into either the mains or another UPS (preferably a
| different brand but identical power). I resorted to this after
| having multiple APC and Cyberpower batteries fail killing power
| (even with a line-interactive APC). I run my network (cable
| modem, router, primary eero AP) off this, no servers. Means we
| can typically stay online even when the power glitches for an
| hour or two after a storm.
| _rs wrote:
| Do they make these that have normal 5-15R plugs on them that
| don't need custom wiring?
| epc wrote:
| The one I bought uses standard NEMA cords and outlets:
| "CyberPower PDU15M10AT Metered ATS PDU"
| https://www.amazon.com/gp/product/B00NEHUX08/ -- it's
| overkill for my use case but was the smallest option I could
| find. I don't have any of the control modules (provide
| snmp/http APIs).
| tx-kun wrote:
| Yeah, all I can find on Amazon are 30A or 50A. I thought it
| would be like those extension cords with timers you use for
| outdoor lights.
| pcdoodle wrote:
| Dell latitude laptops have OEM chargers that can run on 10-16VDC.
| The E6520 I use as a server takes about 6W to run at idle. Grab a
| 12V battery and a 5A SLA Charger, run your router/modem/server
| directly off the battery.
|
| UPS's take about 10W to just power the inverter. This gives up a
| lot of the battery capacity not to mention the losses from
| converting your power 2 times.
| kop316 wrote:
| > I live in a place where blackouts are very infrequent (perhaps
| a couple per year), but occasionally the mains drops out for only
| a second or two. I suspect these very short dropouts occur when
| substation switchgear operates, but have no way of being sure.
| Anyway, with a server running 24/7 I obviously wanted protection
| against any loss of the mains supply.
|
| > So I thought I had covered all bases, and, indeed, the UPS
| proved useful on several occasions. I would quite often be on a
| work trip and receive an e-mail from the server informing me that
| mains power to the UPS had been lost, then another e-mail soon
| after informing me that mains power to the UPS had returned. Only
| once did the power cut last longer than the battery capacity, and
| the server was shutdown automatically.
|
| It sounds like the UPS is doing exactly what he wants it to do.
| This is exactly why I bought a UPS. I would have power transients
| sometimes and rebooting my entire network (with NAS and servers)
| was annoying, and I didn't want it to go out when I was gone.
|
| His main complaint is he bought a standby UPS where the battery
| failed, it turned off the UPS (which is understandably
| frustrating), and now replaces the battery every three years.
| Looking at the white paper referenced, it even says to go for
| Line Interactive for servers. I'm also curious how the person
| knew that power wasn't cut when he was away?
|
| So other than buying the wrong type of UPS (which at face value
| looks to be a valid complain based on research)....why isn't a
| UPS as useful as they'd think?
| xxpor wrote:
| >a standby UPS where the battery failed, it turned off the UPS
|
| I assume this would be because the power is always flowing
| through the battery/inverter? Wouldn't that kill the battery a
| lot faster? Although it'd make the switch from mains to actual
| battery power basically a non-event from the output's
| perspective.
|
| Now that I think about it, going 120/240->low voltage
| dc->120/240->12/5/3.3 is incredibly silly. IIRC there are 48
| (or -48?) DC power supplies out there, mostly for data center
| use. Does anyone make an ATX version that you could hook up to
| a UPS that has a DC output?
| jcrawfordor wrote:
| Using a DC auxiliary power supply for backup is common in
| telecommunications equipment and by extension common in
| network appliances - "redundant power supply" for network
| equipment typically means a built-in AC power supply and then
| DC connections for an external aux power supply that provides
| battery, often called an RPS.
|
| This isn't common for servers though which, if equipped for
| redundant power, have two AC power supplies. I think this
| just comes down to the higher current draw usually associated
| with servers, running even 48VDC power can become costly and
| impractical when you need to supply say a couple thousand
| watts per rack, so the extra space and thermal load of an AC
| power supply in each unit becomes preferable.
|
| The downside is that while redundant power supply is usually
| a "standard" feature on switches and routers (that is, they
| always have the connection whether or not you buy an RPS is
| up to you), you need to specify and pay extra for dual AC
| power supplies up-front in servers, so you don't get as
| smooth as an upgrade path. That said in datacenter
| environments you often buy servers, racks, and power systems
| all at once so it's not as much of a concern.
|
| There's a similar tradeoff that exists around bottom-of-rack
| UPS and central (building or area) UPS---bottom-of-rack UPS
| tends to be more expensive, higher maintenance, higher
| thermal load, etc for large installations, so usually large
| installations use one (or two for A+B power) large central
| units which may be hybrid between different technologies like
| flywheel and battery (and you could view the transfer to
| generators as a "third stage" of a central UPS system), but
| it also makes your cabling a little more complicated and you
| have a bit of an "eggs in one basket" situation. Central UPS
| generally have internal redundancy so their risk of failure
| is low, and often a bypass device where if a non-recoverable
| failure of the UPS is detected a contactor "shunts" the
| entire UPS removing it from the circuit so you don't lose
| power _due to_ a UPS failure, but that doesn 't necessarily
| save you when the HVAC pours water directly into the UPS
| control cabinet causing widespread failure of the control
| electronics... a situation that I have somehow seen twice. I
| bet on bigger installs you can get an external bypass with
| some sort of health monitoring though? If HP/Tandem taught is
| one thing it's that you can always through more redundancy
| into your very special basket.
| snuxoll wrote:
| Standby UPS topologies like the APC Back-UPS lines keep the
| battery out of the loop until a loss of power from the AC
| input is detected, at which point the inverter kicks on the
| the transfer switch takes the feed from there.
|
| This is a design choice from APC, money is on the control
| electronics being powered off the battery meaning a dead or
| missing battery means the entire unit is non-functional.
| Making the unit resilient to this probably costs as much as a
| line-interactive unit, however, so you might as well just
| tell people to get a better unit than make a middle-ground
| solution.
| formerly_proven wrote:
| I have a line-interactive APC and it most definitely is
| just a UPS-shaped brick without a battery. Might have
| changed in newer models, I wouldn't know.
| Ndymium wrote:
| As a person who has never bought a UPS, this behaviour of
| turning off power when the battery dies even though there is
| mains power is unintuitive, and I would have most likely hit
| the same issue. I see the post title as a PSA, in that if you
| happened to buy a standby UPS without knowing better, it might
| not be that useful if you very rarely have power interruptions
| but the battery keeps dying every couple of years.
| kop316 wrote:
| Trust me.....having infrequent power outages like that are
| very very annoying. Everything turns off and I have to spend
| a non-trivial amount of time bringing my network back up
| (first router, then NAS (encrypted to I need to hand jam in
| the key), then servers that depend on NAS (also encrypted)).
| What eventualy got me to get a UPS was during a storm, it
| happened twice within an hour! This isn't even talking about
| if I were away, now my servers are down and I have to do it
| when I get home.
|
| That UPS was well worth it to put a stop to that happening.
| bluedino wrote:
| >> His main complaint is he bought a standby UPS where the
| battery failed, it turned off the UPS
|
| As a small business network/systems admin, I've had more failed
| UPS's bring things down than I can count. It's very common.
| Covzire wrote:
| I ran into an extremely perplexing problem a few years ago
| where shutting down one server connected to a UPS would kill
| the entire network until the server was brought up again. The
| server was not providing any kind of networking at all, no
| DNS, DHCP, routing, etc.
|
| After wasting a lot of time remotely trying to diagnose this,
| it was obvious what was happening once I got on site. It
| turned out that once this server was shut down, the UPS
| didn't have enough power draw to power the other equipment
| attached to it, so a switch that was plugged into the same
| UPS would shut down as well. For some reason it had failed in
| such a way that it required a certain level of draw for it to
| function at all.
| jaywalk wrote:
| Some UPSes have a special outlet on them that when it's not
| drawing power, it intentionally shuts off the other ports.
| It's meant for power saving, but I've seen more than one
| person get tripped up by this functionality.
| Zancarius wrote:
| That reminds me of a "feature" in many of the consumer
| grade UPS units on the market now. I don't think it's
| enabled by default, but they do have an option to power
| down the UPS when the primary outlet is no longer seeing
| any power consumption.
| kop316 wrote:
| Heh, interesting. Is it a specific brand or model (i.e. I get
| what I pay for), or this just a thing with UPSes?
| michaelt wrote:
| _> I 'm also curious how the person knew that power wasn't cut
| when he was away?_
|
| Most homes have _something_ with a mains-powered, non-battery-
| backed clock. You get home and the microwave or the oven is
| flashing 12:00 and you know there was a power cut.
|
| _> So other than buying the wrong type of UPS_
|
| This isn't a failure of 'type' of the UPS - it's a design fault
| deliberately left in by the device manufacturer for market
| segmentation.
|
| It would be trivial for them to keep the power outputs on if
| the battery failed but the mains remained on. Leaving it out is
| a business decision, hobbling their home product so it doesn't
| steal market share from their small-business product.
| Havoc wrote:
| Generally line interactive is less preferable since they provide
| less protection from surges than a double conversion setup. Big
| price difference though so line interactive is usually a
| reasonable compromise.
| snuxoll wrote:
| For a home setup you aren't going to be spending the money a
| double or delta conversion unit costs, so line-interactive is
| the only sane choice.
|
| You really don't want line-interactive gear when dealing with
| larger loads either, as the transformer will just cause extra
| current draw during a voltage sag. This is why you don't see
| (many of) them above 3-5KVA.
| linsomniac wrote:
| Automatic Transfer Switches feel like a requirement for using
| UPSes to me now. Either that or redundant power supplies. I've
| had too many UPSes, both the BackUPS and the higher end SmartUPS,
| cause more downtime than they prevented, over around the last
| decade.
|
| When we moved offices 3 years ago I pulled our UPSes out, because
| all the outages the previous 5 years were caused by the UPSes.
| smiley1437 wrote:
| Genuinely curious - what strategy do you use for unplanned
| power outages if you don't have a UPS? Just deal with the
| potential corruption?
| Johnny555 wrote:
| But then your ATS becomes another potential point of failure.
| If you have so little trust in your UPS that you need an ATS
| behind it, I think you are probably better off without the
| UPS's.
|
| In my last job I had around 100 APS SmartUPS's (mostly 3KVA) in
| various wiring closets and in the ~3 years that I was there,
| none of them failed unexpectedly, but we had to replace a few
| batteries and/or entire units when they failed their monthly
| self check.
| guerby wrote:
| If your devices are low power like a NUC, recycled laptop,
| DSL/fiber modem or NAS they'll likely accept 12V as input (or
| 12-19V for most Intel NUC for example).
|
| For these I wonder if instead of a UPS: buy two LiFePo 12V
| batteries with included BMS, two battery charger (AC to 12V DC),
| so you get a redudant 12V bus where to plug your devices.
|
| If above 12V is needed add two DC-DC converters eg 12 to 19V to
| add a 19V bus. Same for 5V.
|
| It shoud work and support failure of any one of the parts?
| esaym wrote:
| Kind of a lame article. He is complaining about his $50 consumer
| grade UPS. The minimum any server needs is the Apc SMT750 "Smart-
| ups". It takes two batteries, cheap ones last about 3 years, the
| replacements from APC can last between 5-7 years. But the unit
| can supply mains power with no battery connected and the
| batteries can be hot swapped easily from the front of the case.
| These are $300 new, but you can find them used on ebay between
| $50-$100.
| amelius wrote:
| Why is that lame? My smartphone has compute capabilities that
| come close to my home PC's, yet it has a battery that's much
| cheaper than $50.
| mm89 wrote:
| I also have an APC Back-UPS. Mine are the Back-UPS 650 model, I
| have two of them. Both emit an annoying LOUD high-frequency
| capacitor whirring noise that is audible to my ears even when the
| loud AC intake fan is blowing in the same room. I'm actually
| shocked any company would ship a product in this condition,
| unless all their customers have hearing problems. It's a power
| strip... it's supposed to be silent. Not like a computer.
|
| If my batteries die, I'll just replace them with non-battery
| backup strips. Not worth the trouble for me living in a city
| where power goes out maybe once per year on average for 10
| minutes, and I don't have servers that need to stay online
| anymore.
| linsomniac wrote:
| Anyone used those new LiPo UPSes? Wondering if they have a longer
| useful life than the lead acid, but haven't used them. Thought
| about getting a PowerWall for our new office, but they don't
| start providing power for 3-5 seconds after the utility power
| goes out.
| mirimir wrote:
| I've always used line-interactive aka double-conversion UPS. Both
| because of the battery failure issue, and to protect equipment
| from crappy generator power. Basically there are rectifier and
| inverter circuits, with batteries on the DC side.
| tx-kun wrote:
| I was doing some researches about this very topic a couple of
| weeks ago and saw a post on Speciesworks (still trying to find
| the post). In that post, one Eaton rep replied that the ups
| device would shut down once the battery died to protect the
| devices connected to it.
|
| Teah, it's just this simple. This is just a byproduct so all
| those companies can boast their insurance coverage on damaged
| equipment you connected to their UPS. And guess what, most of the
| time you won't be able to get this insurance even if your stuff
| got fried, saw a few stories like these from recent Slickdelas
| posts of UPS.
| samcheng wrote:
| With all of the recent advances in Lithium-type battery tech
| (e.g. 18650) it seems like a market opportunity to create a new,
| modern, small, smart UPS.
|
| These low-end APC dinosaurs still use lead acid, and in my
| experience (with a solid utility over the past decade) outages
| are just as likely to be caused by battery failure than some kind
| of actual power outage.
|
| If anyone wants to build something better, happy to chat further.
| t0mbstone wrote:
| Portable power packs are crazy cheap these days. You can get a
| 20,000mAh pack for $45 quite easily. They are almost always
| Lithium Polymer based, and are very small and light. I have had
| one sitting in my bag for almost a year now and it still has
| most of its charge.
|
| What I don't understand is why it would be so hard to just
| scale those power packs up a little bit and slap a normal 110
| volt A/C plug on them? Wouldn't that essentially be a super
| efficient, light weight UPS?
|
| I did a bit more digging and I found a couple of portable power
| packs that offer this sort of functionality:
| https://www.nytimes.com/wirecutter/reviews/the-best-portable...
|
| What I don't understand is why they are so expensive, and why
| they can't seem to scale them up to the same size as a normal
| lead acid battery UPS?
| floatrock wrote:
| Main advantage of lithium-ion over lead acid is lithium-ion is
| more energy dense so you can have a smaller size at a smaller
| weight. Important if you're building cars, but the price
| premium probably isn't worth it if you're building another
| office box at commodity pricing.
|
| Edit: Since we're armchair-building for a predictable, high-
| uptime application, failure modes might have an interesting
| advantage though. Any battery engineers know if lithium ion has
| more predictable or measurable failure modes? Yes, we've all
| seen the exploding hoverboards... I'm assuming theoretically
| well-built electronics.
| thescriptkiddie wrote:
| Lithium batteries have a much longer lifespan than lead acid,
| which would eliminate the need to replace UPS batteries every
| few years. They are also more power dense, so if the goal is
| just to keep a machine running long enough for a clean
| shutdown, you can get away with a smaller (energy and size)
| battery for the same load.
| martinflack wrote:
| It could possibly target the "Apple-esque" product category
| by using a smaller physical footprint to emphasize sleek
| looks, perhaps with a small sharp readout. The small size
| could be leveraged further by only attempting to provide
| power for a short amount of time, say 10 minutes, emphasizing
| and _requiring_ USB connectivity to shutdown the protected
| computer at minute 9.
| jimktrains2 wrote:
| I thought the main advantage of lead acid or gel cell vs li-ion
| is cost, recharge cycle, and the ability to provide high
| amperage.
| t0mbstone wrote:
| I don't understand how lead acid has an advantage in recharge
| cycles? My lithium batteries can be discharged and recharged
| over 1000 times before they wear out, and they hold a charge
| for ages. My UPS with lead acid batteries, however, is
| practically useless after a single full discharge, and the
| batteries have to be replaced practically every year.
| jimktrains2 wrote:
| Sounds like a bad ups. Lead acid batteries can be
| discharged pretty far while still being rechargable..the
| same can't be said for lihion.
|
| Car batteries are lead acid/gel cell batteries. They last
| for years and can take a very large discharge while still
| being rechargable.
|
| Also, by cycle I meant a single vharge-discharge cycle can
| be more useful when larger amperage or more power is needed
| between charges.
| samcheng wrote:
| I'm not sure the cost advantage of lead acid still holds,
| especially with the e.g. shipping and disposal costs
| included.
| jimktrains2 wrote:
| There is a reason we don't see lihion car batteries, or
| fork lift batteries as a default. (Yes, Tesla's are li-ion,
| but that's a scale where the weight savings begins to
| matter. Iirc those battery packs can't deliver peak
| amperage quickly or many times in their life, e.g.
| ludicrous mode.)
|
| Additionally, li-ion has non-neglegable disposal costs, so
| I don't think it's fair to count that solely again lead
| acid batteries.
| gsich wrote:
| In fork lifts it also acts as a counterbalance.
| sparc24 wrote:
| I ended up in India during the lockdown. Power outages are
| frequent and so are voltage fluctuations. Most people have a
| generator. Most houses haves 3 phase power coming in. Basically
| anything over 3 kvA the utility guys put in 3 phase at 415V - 3
| hot and a neutral. About 3 weeks ago we lost neutral which
| resulted in double voltage both my MBP chargers got fried
| including the long extension wires which are super useful. It
| also took out an AC, a refrigerator, 2 air purifiers. Anything
| connected to the BackUPS did survive including the 65" oled tv.
| Luckily we managed to fix all of fit with simply replacing the
| PCBs. Being stranded with my laptops would really have sucked.
|
| Since I am stuck here til next July I started fixing some of
| this. More than anything else power conditioning was the single
| most important thing. Anything with any reasonable switch-mode
| power supply will be fine on a line interactive UPS, most people
| don't need to spend $ on an online UPS - esp if your power is
| fairly clean. We had old locally made generator so I finally
| replaced that with a nice single phase 25kVA generator. The
| alternator has voltage regulation. For the mains power I was told
| most people just put a Servo Stabilizer but I didn't want any
| moving parts so found an IGBT based static stabilizer instead.
|
| http://anjalipowersystem.com/static-stabilizer.html
| https://download.schneider-electric.com/files?p_File_Name=JS...
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