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badabing1

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APC UPS Question?

Hi,

I need to know the following please-

All my servers have dual power supplies, one plugged into UPS and one plugged into the wall socket.

My question is its seems as though the primary power servers are using from UPS, i would prefer it to be used from main socket on the wall, and if the power fails then UPS kicks in??

Is there a setting i can do on the server to get it to do this, as i have not configured anything under ups setting on windows?

cheers
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Gary Case
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No -- there's no way the server "knows" which power supply is plugged in the wall vs. the UPS.    There's also no reason to do what you've indicated -- the UPS doesn't "kick in" until there's a power outage;  and meanwhile it provides FAR better surge protection than you likely have on your wall outlets.

I'd simply plug both supplies into the UPS, so you'll have maximum protection against surges, brownouts, etc.

If you want to keep your current config, simply switch the power plugs ... this should provide the "normally from the wall" draw you've indicated you'd like to have.
>i would prefer it to be used from main socket on the wall

With a modern UPS, you're not going to save any significant amount of electricity.  I doubt you could measure it.  But...moot point, since redundant power supplies are designed to all run at the same time.

How are you determining that only one cable is drawing power?  That seems to indicate that the PSUs aren't working as designed.
"... With a modern UPS, you're not going to save any significant amount of electricity ..."  ==>  Actually there will be ZERO savings.      The UPS is already on in the scenario noted above, so the very minor control logic draw is already happening.     And unless there's a power outage and the inverter kicks in, there's no actual draw from the UPS ... it's just passing it through from the wall.     As I noted above, I'd just plug both power supplies into the UPS.

... as for whether or not the PSU's are working as designed -- it depends.    Many systems with redundant supplies will only use one supply as long as the total current demand is modest.    This is generally more efficient.    It's easy to measure the actual draw of each line with a simple Kill-a-Watt or equivalent.
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badabing1

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the reason i say its drawing power from UPS is, we had a problem with our Air con system which kicked in servers fans at max, we then started to get alerts from APC UPS "batteries discharged" what this meant to me was that the load on UPS was at max hence the alerts, as soon as room got cooler the fans settled down and the load on UPS came down.

so this is why i need to know a way around if at all possible?

Thanks
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Gary Case
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i think we had it for about 3 years..and yes the electric was still on? could it be that its overloaded, load lights are 4 and sometime jumps to 5?
It's possible that it's overloaded ... but that still wouldn't explain the failing battery.
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thanks