Mining hardware and battery backups (UPS)

[KIDC]

So I've run a couple of dedicated mining rigs using GPUs for about 9 months, have recently added one BFL Single with 5 more on the way, a 6 BFL SC Singles coming (whenever they're released lol). To make a long story short, I can't run BAMT or scripts on my boxes, I have to run Windows with system drive encryption. In all the properties I've lived in here in FL there's these once a week at least 1-3 second transient power drops that cause all my hardware to reboot and sit idle until I get physically sit back down at it and get it all started up again. This usually takes 8-16 hours before I can get to it.

So for this reason and with all this BFL hardware coming I finally dropped $200 bucks on an APC BX1500G 1500VA battery backup at my local Staples yesterday. I connected everything up and everything appeared to be working perfectly. However I noticed pretty quickly that one of the GPU miner boxes now crashes (video output just freezes, unit stops mining) every 30-120 minutes. It uses about 180W at load, has a single 5850 @ 915/300 (stock volts) and uses http://www.newegg.com/Product/Product.aspx?Item=N82E16817371033 for the PSU. I've had no problems with that PSU and it work's perfectly. I did notice right when I setup the APC UPS that that PSU makes an odd audible buzzing noise when it's running off battery power.

So my question to you, fellow miners, is why does it do this? I don't understand why it would do this. I haven't had any problems with the HP Slimline tower that the BFL Single is connected to (or the BFL Single itself), or the other self built media server that I run off the same APC unit (it has a 380W SeaSonic PSU). Unfortunately I don't currently have the 7970 in the other dedicated GPU miner box because I'm prepping it for sale. However once I have to stock HSF back on I'll try that out too.

I haven't had a lot of time to look at this issue yet but it's already crashed like 4 times and crashed in the night as well as shortly after I restarted it at 6PM.

Any ideas or suggestions would be appreciated. I have not had a chance to call either APC or Antec yet.

My other major concern is if running this battery backup is going to damage or destroy the hardware I have connected to it - specifically 6 FPGAs (and then 6 BFL ASICs). Running all the ASICs off this battery backup is the primary reason I spent money for it (money I could barely afford).

Thanks,
KIDC

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[CA Coins]

I run 5 APC BR1500 1500VA UPS for my FPGA cluster.  It is good for providing continuous/modulated power; however, the 1500VA is really only good for about 700 Watts of power to the GPU/MB/etc.  It's rated for about 850 watts, but counting PSU/UPS inefficiencies, it won't give your GPUs 850 watts.  To be safe, I run them at about 650 watts each and is stable as a rock.  If you're hooked up to the battery, and you go over the battery maximum, it will cut power (overload).  To see if you're overloading the battery, you can try plugging it in to the surge only plugs to see if your GPUs are still crashing.  If that doesn't solve your problem, then it may be a defective UPS.

[KIDC]

I only actually draw no more than 400 watts so overload shouldn't be the problem. I think it's something quirky with just that one Antec 380W PSU; I put the 7970 in the other box and it's run all night without problems. Only that one box with the Antec PSU has problems - the rest are Seasonic or Corsair (rebranded Seasonic) with the exception of the HP Slimline which is just an OEM unit. That's also working without any issue it seems.

Still not certain if my hardware isn't being slowly damaged. A lot of people run these UPSes so it should be fine I would think - then again if it was exactly the same power then why is the Antec so unstable? Odd.

Thanks for your feedback CA Coins. I'll try just the surge only on the problem box and see what happens.

[CA Coins]

You're welcome. It can certainly be the PSU, but UPS should be pretty safe.  Good luck.

[n4l3hp]

Where I live, we have these few seconds power loss quite often. Will a device like this help?

http://www.ebay.ph/itm/Electric-Saver-Power-Factor-Save-Electricity-KVAR-1200-/390144826453?pt=LH_DefaultDomain_0&hash=item5ad6719c55#ht_8045wt_905

As I understand the purpose of devices like this is it has the capacity to store power for several seconds and also help save power especially if using devices with motors. Does it really work as claimed?

[Graet]

I decided I couldn't afford to UPS all my rigs. So I set them to reboot on power failure and added cgminer to startup programs. Along with teamviewer most power related downtime is minimised

[jkminkov]

I noticed that switches are vulnerable to power spikes - some rigs can reboot, some would keep mining - but switches just hang bringing down communications for all rigs, so I put all mine on a small ups

[vapourminer]

that one rig that crashes.. it only crashes while on battery power?

also, i should think the PSU shouldnt make abnormal noises while on battery, I have 3 rigs on APC UPSs and none make noise (one is an antec earthwatts 650 green).

try swapping the power cord on the noisy PSU, they can go bad (corrosion on the plug, internal fraying etc)

[KIDC]

Thanks for the continued advice guys.

To update you, as of a few days ago I stopped running both GPU miners because I'm selling/reusing the GPUs in them. I found out that the miner box with the Antec PSU was never stable on the UPS, even if it was on surge only. It froze up on idle too, however it took a lot longer (about half a day). The other miner box worked perfectly as does the BFL Single and the media server, both have been running now for almost 3 weeks with no issues whatsoever.

So unless by 5 Singles that are on their way via USPS have problems with this UPS, I'm going to call it case closed for now. I'm out of the return period for it now anyway - I may follow up with Antec and/or APC sometime regarding these issues but I'm going to be moving the BFL Singles to a different room where they'll be the only thing on the UPS anyway, and I'm assuming the power bricks that they ship with will work fine as the current one does.

Thanks again for your insight everybody 

[fabrizziop]

Well, your UPS is only line-interactive, meaning it normally has an auto-transformer (transformer with only one winding, no isolation), with several taps to compensate for slight over-voltage(normally up to 140V) or under-voltage(normally down to 90V), to get your line voltage closer to 120V. This is very common in consumer UPS appliances, as it's cost is lower than an online UPS. When the power goes above or below the capabilities of regulation of the auto-transformer, it switches to battery power, giving an "approximation to a sine wave". That doesn't look like a sine wave, but it works in 99.99% of equipment as it maintains the same peak voltage and compensates the width to maintain a close RMS voltage to the nominal one. There are myths telling that PSUs with Active PFC don't work with pseudo-sine wave UPSs, but that's normally a lie, you may experience buzzing at most on those PSUs when running on batteries. If the UPS was interfering, it should only fail when you experience a power failure, not on normal filtered line power.

On the other hand, there are online UPSs that rectify and invert the power, making the power 100% clean always, and your computer is isolated from the grid, so in the case of severe interference/lighting strikes it's very unlikely you'll get damage. But that comes at a huge cost, those units for about 1000 VA are about 200-300$ new, although you can find them sometimes on eBay/geeks.com at 100$ refurbished.

Personally I got a true sine-wave UPS from eBay, at 60$ used with no batteries, and then got two 130AH deep cycle batteries. I use the UPS for my main rig and a small mining rig, and I get like 8-10h at least without mining.