Home Power Issue- New Server trips breakers!

Z

ZXQ

Limp Gawd
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Jul 22, 2004
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Pacificgeek.com had a 1 day sale a few weeks go for Dell SC1425 systems for $100, so, I jumped on it, and bought 4.

Well, on day one, 2 of them came in, and I decided to install them in my office, along with my Power Edge SC440, and 2 gaming systems (700w PSU feeding a i7 920/ATi 5800, and a 650w feeding a C2D and ATi 4850). I plugged them into my UPS (APC Back-UPS ES, 6 outlet 350VA, 120V ) and everything was great for about.... 5 minutes. Then the room went black, and my UPS started screaming.

Anyway, I shelved them for a while, assuming the worst, that I had too much power being pulled in my office, and well, I have no space anywhere else for them at the moment.

Fast forward to last night- a buddy called wondering if I would part with 2 of them. Sure, so, I decided to test them all, and also decided to do an experiment. I shut down EVERYTHING in my home, and started plugging one of the servers into an outlet in every room. Room after room, I was tripping breakers, with just this single server. I tested all 4 of them, and produced the same results.

I was a little hot at this point.

Then I got the wild idea to try out an outlet in my garage... and BAM, no issues. Tested all four of them, thankfully, they're all fine, but I'm baffled. NONE of the circuits in my home can handle 1 SC1425? This isn't some powerhouse server.

So I did a little research on the servers.

Went to Dell's site, and decided to pull up the papers on these things power consumption. I saw one line that kinda made me do a o_O?

"Under typical line conditions and over the entire system ambient operating range, the inrush current may reach 40 A per power supply for 5 ms or less and 60 A per power supply for 1 ms or less."

Ok, so, at any given time, these things can suck down 60A for even 1ms? Just enough to trip my breakers? I assume this occurs at start up, which is when these things go *splut*.

Is there any way, short of getting my home inspected, and having an electrician come in and install beefier circuits? Would a better UPS condition for these small spikes? I don't know jack about the intricacies of electricity, and any guidance would be great.
 
That UPS is tiny, no wonder it went nuts.

How old is you breaker panel? Breakers can wear out if they've been tripped a lot.
 
Oh, should have stated- House was built in 2003. Were talking fairly new stuff here. (Compared to a home built in the 70's, I mean.)

And yeah, I know the UPS is tiny. I use it just for power flickering when we have thunderstorms in good Ol' Oklahoma. Blarg.

//edit: And I should also state, that I never checked the breakers themselves for spec labels. Doing that when I get home from work in 2 hours. I'll post my findings as well.
 
The APC ES350 series suck.
The whole ES lineup sucks.
We're huge APC fans..that's pretty much all we use, but ever since those budget ES series came out...they just don't seem to last even a year with a simple desktop PC plugged into them..even the ES550. I use the ES350 for network hardware...broadband modems/routers/switches...but for a desktop and monitor, we no longer use them.

Now plug a few servers into them? Wow...I can certainly see it killing the juice in 1 minute...even with just a glorified desktop sc440.
 
YeOldeStonecat said:
The APC ES350 series suck.
The whole ES lineup sucks.
We're huge APC fans..that's pretty much all we use, but ever since those budget ES series came out...they just don't seem to last even a year with a simple desktop PC plugged into them..even the ES550. I use the ES350 for network hardware...broadband modems/routers/switches...but for a desktop and monitor, we no longer use them.

Now plug a few servers into them? Wow...I can certainly see it killing the juice in 1 minute...even with just a glorified desktop sc440.
Click to expand...

It seemed to handle the SC440 and my network gear just fine for the last, eh, 12 months?

But thanks for the heads up on the ES shenanigans.
 
I find it hard to believe that a sc1425 could have a inrush current that big. That would trip a single circuit on any PDU that I use or have used. Hell that would trip some entire pdu's.

Try booting them up with less hardware inside (for testing) / only one psu (if they are redundant), to see if it makes a difference.
 
60A for 1ms or 40A for 5ms wont trip a standard residential breaker. These breakers use thermal overload devices that have a time overcurrent characteristic. In other words, the more current, the faster they trip. However, you can run the circuit at 100% for quite some time before it will trip. Even at 200%, it'll take at least a minute to trip.

Ah, just had a thought. Do you have GFCI or AFCI breakers? If you have GFCI breakers, there could be a ground fault in the PSU that's tripping the breaker. If you have AFCI breakers, the inrush could be fooling the arc detection circuitry into thinking there's an arc fault.
 
That server should only be pulling 4 amps and maybe a little more on power up. I would try #1 a different power cord #2 an electrical tester to make sure the electrician didn't flip hot/neutral wires or not connect the grounds. I have seen some nasty stuff in houses of all ages, inspectors don't catch everything.

Could be your breakers just don't like the "inrush".
 
So this begs the question, what's different about your garage plug? Would you say it's closer to the breakers than other plugs you've tried? I bet it's not as daisy chained as some of the plugs in your house are.
 
They're all AFCI?

damn, someone spent some money. You only need those for bedrooms by code.

The garage will be on a GFCI, so thats the difference.
 
valve1138 said:
They're all AFCI?

damn, someone spent some money. You only need those for bedrooms by code.

The garage will be on a GFCI, so thats the difference.
Click to expand...

I'm sorry, my comment was misleading. Was tired when i got home from work.

By "They're all AFCI" I meant every outlet in the house, not every actual breaker. (Breakers for the stove, A/C, Heat, etc, are QT or QP typel).

And incredibly sorry about the garage breaker description- I went back and checked out that outlet. Apparently it's on the laundry room circuit, which is a 20 QT. I have got no idea where i came up with that 40 paired crap.

PSA to the H, don't try to give accurate descriptions while tired and pissed.
 
Looks like you have two choices if you want to be running those servers in your house.
#1 find plain 20amp breakers that fit your panel and swap it with the circuit you will be running the servers on (shhh, don't tell the city, but your house was built before 2008 so eh...).
#2 (and i'm not sure if this would even work) Find a power conditioner that can handle the load, but there went the savings on the servers... It looks like you're due for a new ups, one with AVR may fix your issue too. You could always return that avr ups if it doesn't work out.

I base #2 on hunches not facts, someone smarter than me please comment.
 
I just googled "AFCI and computer power supplies" and got at least 10 results that seem to have problems with computers plugged into AFCI circuits. While I didn't click thru to the links, I'm willing to built that most of these are AFCI breakers that were manufactured when AFCI first came out. From what I heard there have been many issues like this with AFCI breakers. The microprocessor inside the breaker uses an algorithm to determine when the circuit has an arc on it. This algorithm and detection process sucked when AFCI was first introduced. I don't know if the problem has been sufficiently corrected yet.

Anybody care to comment of whether they are having this problem with a recently purchased AFCI breaker? I think I'm going to go buy and AFCI breaker and install it on my server circuit to see if I can replicate the problem. This could be very interesting if this is conclusive.
 
ZXQ said:
I'm sorry, my comment was misleading. Was tired when i got home from work.

By "They're all AFCI" I meant every outlet in the house, not every actual breaker. (Breakers for the stove, A/C, Heat, etc, are QT or QP typel).

And incredibly sorry about the garage breaker description- I went back and checked out that outlet. Apparently it's on the laundry room circuit, which is a 20 QT. I have got no idea where i came up with that 40 paired crap.

PSA to the H, don't try to give accurate descriptions while tired and pissed.
Click to expand...

So you've got a Square D brand panel?

Shit, those are tanks. I'd say it's the AFCI issue.

Maybe try a beefier UPS or if that doesn't help get an electrician out to check out the AFCI breakers and see if they're the older ones.
 
valve1138 said:
So you've got a Square D brand panel?

Shit, those are tanks. I'd say it's the AFCI issue.

Maybe try a beefier UPS or if that doesn't help get an electrician out to check out the AFCI breakers and see if they're the older ones.
Click to expand...

I'm going to go the UPS route. Moving in a few months, might as well get something I can take with me first.

Thanks all for the research/opinions. Helped out a ton.
 
I doubt a UPS will solve the problem, unless it isn't the line-interactive type. Most consumer UPS's are "line-interactive" which means the loads are connected directly to the wall outlet unless the voltage coming from the wall outlet is out of spec (too low, too high, etc.). A line interactive UPS will not stop the signal that causes the false trip from getting to the AFCI breaker. Unfortunately the only solution seems to be to find a power supply that doesn't offend the AFCI, or removing the AFCI completely (possibly a NEC violation). You could also install a newer AFCI that has better detection algorithms.
 
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