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Berkson WeinFlag for United States of America

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Electrical Problems - all units turning off

We've got a strange situation.  Have a client who previously had a couple of computers and a dsl modem connected to an APC backups 1100va battery.  The battery seems to work ok.  There were a couple occasions where everything would suddently turn off though, even without a power outage.

It wasn't worth fighting or diagnosing.  They started using a APC SmartUPS 1500, that was used but with relatively new batteries.  The strenth indicators show at about 90%.  The crazy thing is that the problem is back!

Can anyone think of something that would cause a battery and all downline equipment to just turn off?  Even if the outlet is bad, shouldn't the battery keep the equipment on for a bit?  We've tried pulling the plug from the wall and the equipment does stay on.

Thoughts?

Thanks
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Rob Hutchinson
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Is the outlet that the UPS plugged into controlled by a wall switch?

When does the UPS turn off, at night?

Since it's an APC UPS, you should be able to download software( or it came with a CD) that will let you monitor the UPS using software.
On another thought, check to see what UPS you need using this APC UPS selector:
http://www.apc.com/tools/ups_selector/index.cfm
I had a client last month that had their computer power off every time they flipped the light switch. Replaced the APC with a "new" unit. No more problems. A UPS is one of the things I never buy used. By the time you find out it's defective you won't be able to return it.

Possible scenario:

1. UPS is overloaded
2. something in the electrical system causes noise/drain on the circuit
3. UPS attempts to kick in, but (see #1)
4. load exceeds battery capacity
5. UPS powers off instead of powering load

If you could get the load to it's peak, then do the "unplug" test you should have the same result.  Unfortunately, how you reach that peak is a mystery.  Do you have equipment or drives powering on at different times?  Laser printer or other high-draw equipment plugged into the UPS?  At seemingly random times (like printer maintenance or warm-up cycles), the UPS would be overloaded.

Noise on the circuit can be caused by CFL bulbs or incandescent dimmers that are near or over their load rating.  I have a 600W dimmer with 6x100W bulbs.  Every time we turn the dimmer on, the UPS squawk for a couple of seconds.
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Thanks all for chiming in.  

There's very little on the UPS.  There's a Poweredge 850 (1u server) with 2 sata drives, a supermicro 1u server with 2 sata drives (300w power supply I think), a basic unmanaged 10/100 24 port switch, and a dsl modem.  That shouldn't be too much should it?  

The suggested PC site says that a 1000va unit is at 57% load and a 2200va unit is at 17%.  This is a 1400va unit so I'd think it would be fine.

There's no printers or other high draw devices.

The UPS is not plugged into a switched outlet.  It runs good for days and weeks, but sometimes just fails.

Uplugging the UPS when it's running normally keeps everything running without issue.

There are no dimmers or CFL bulbs.

It's as if it's just shutting off.

I'll have to see if there's a serial cable around that could be used to check any sort of logs.

They're tempted to just replace the UPS with 2 separate UPS's with enough capacity, but:
1) Budget is a big concern - this is a charity and
2) I'm concerned that it could be a problem with either
   a) one piece of equipment that is somehow shorting the ups out or
   b) and in-wall electrical problem that's forcing the UPS to shut down to protect itself.

On 2b, my client has been there in the past when this has happened.  There's no power outage, not even a flicker, it just turns off immediately.  Once it started a contant beep, once it just turned off without sound.
The continuous beep still points to an overload, either currently or due to damage from a previous overload:

3.)Capacity Overload
¿ Constant, Solid Tone (the red Overload LED will be illuminated)

Meaning:
This alarm indicates that the UPS has detected an Overload condition. If this alarm is sounded, try removing non-essential equipment. The alarm will remain until the load is reduced. To determine if your UPS is capable of handling the equipment you want to protect, visit APC's Sizing Guide at www.apcc.com/sizing.

If the Back UPS emits a constant flat tone and reducing the load does not solve the problem please try the following steps:

1) Turn the UPS off.
2) Unplug all the equipment from the UPS
3) Unplug the UPS from the wall outlet
4) Push and hold the power on button (you will hear two beeps) release the button before the second beep ends.

At this point, the UPS will either go into battery and work fine or it will continue to emit a constant flat tone. If the unit still emits this tone, it is an indicator that the UPS was permanently damaged due to the overload. Please contact APC at 800-890-4272 for a replacement or visit APC's Sizing Guide at www.apcc.com/sizing 

http://emea-en.apc.com/app/answers/detail/a_id/480/~/causes-and-solutions-for-a-beeping-apc-back-ups-product
PE850 has ~350W PSU.
SuperMicro with ~300W?
Switch with ~250W max (I have a Netgear 24port with 2A@120VAC)
DSL modem with ~30W.

Even rating these at max, that's 930W.  A 1400VA unit on 120VAC should be fine (near capacity).  But I've never seen any equipment actually drawing anything _near_ 100% of PSU rating.  Even startup on servers (with all fans running), you don't spin up the drives at the same time.

Plus...with an observer, you'd notice that all of your equipment was trying to re-start at the same time.  But you have to trust the on-site reports.  I've gotten bad reports, often from the on-site person making sure that he/she would not be blamed.

On one occasion I watched a tech push the on/off button of the UPS when it was squawking for attention.  Instant shutdown.  But the tech's intention was just to silence the alarm.  He said, "Something must be wrong with the UPS, because it's not supposed to shut down."  Had I not been standing in the room, I'm sure he would have dreamed up some story about a self-destructing UPS.

aleghart-
Thanks for the info -
we're on the same page here, it's just strange that this is happening with 2 different UPS's.  I've never seen it happen anywhere.

When the tone was sounding solid, all servers were off (because the UPS cut the power to them), so you'd think the load would be zero.

Tonight, when the director came back in, everything was off, no tones, no lights on the UPS, nothing.  It was as if everything was shut down intentionally (which it wasn't).  This is typically how the problem presents itself, no sounds just all off.

I'm going to recommend 2 new 1000va batteries to replace the single one, I'm just afraid that it's something else like a short or something, but can't imagine what that would be...
I'm just afraid that it's something else like a short or something, but can't imagine what that would be...

that is a possibility : a short in the wiring..
Update:

I had the client remove the UPS from the production environment.  No UPS is better than one that shuts off at random.

They kept it plugged in and on overnight, but with no devices being powered by it.  When they came in this morning, it was off.  The other devices that were plugged into the same outlet remained on overnight.

It's now plugged into a different outlet in another room that is theoretically on a different circuit.  We'll see if it stays on.

The crazy thing is that this happened with the UPS that this new one is replacing, so I'd agree with nobus that a short could be possible somewhere.  However, if this is the case, I'm surprised that the surge protectors that are on the same circuit aren't cutting out.

Other thoughts???  THanks
Surge protectors don't have sensors and a logic circuit behind them.  They fail or they don't fail.  Transient problems will pass right through.  And most computer equipment will take a tiny transient and just deal with it.

>They kept it plugged in and on overnight, but with no devices being powered by it.  When they came in this morning, it was off.

Still 50/50 that the UPS is bad or a site wiring/supply problem.

Just curious...after problems with a flaky UPS, why did they choose to procure a used model?  What is the warranty situation?
Good points and questions aleghart.  This is a charity.  They're national, but have a low IT budget.  They found a local donor who had a gently used 1400XL and who was willing to donate it.  There's no warrany, but it was free.  Unfortunately, budget is a serious driving force for a lot of the decisions.

They're not beyond buying a new UPS, I just don't want to recommend it if it's not going to solve the problem.

They might be able to get an electrician from the building in, but I don't even know what to have them check for.  
oh, and shouldn't a SmartUPS 1400xl come back online after whatever problem had it shut off goes away???
>shouldn't a SmartUPS 1400xl come back online after whatever problem had it shut off goes away?

Should.

There is a setting that would alter that.  "Minimum Capacity Before Return from Shutdown" could be user set as high as 90%.  So, if the battery pack is not re-charged to at least 90% after a discharge/event, then the UPS will not automatically resume operations.  The factory default is 0%, meaning that the UPS will power on as soon as it detects mains power, regardless of the battery charge level.

If the UPS controller is damaged or firmware is corrupted, then it will behave unpredictably.  It doesn't sound like an actual load problem, or else you'd see it power up, or find a pop-up circuit breaker tripped on the rear of the unit.  Plus, you've plugged it in with zero load and had the problem repeat.

Have you monitored the UPS logs yet to see what it's been reporting?
Here's the manual, for future reference:

http://www.apcmedia.com/salestools/ASTE-6Z8LGY_R0_EN.pdf
Of course there's no serial cable connected to the unit.....

If the minimum capacity is set to 90% and the batteries are old enough to never quite get to 85%, that could explain it.  

Still, I feel like it's wiring related.
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aleghart
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even if the ups comes on again - the pc's would neet to be set to pwr-on after power-off
keep troubleshooting the short...
fyi, the pc's do power on when there's power.  These 2 ups's are turning off, thereby cutting power.
It looks like to original owner messed with the firmware settings!  Thanks for all of the feedback.
Glad you got it solved!  For reference, what were the offending settings?