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Using two UPS's for Dual PSU DL380

Simon Blain
Occasional Contributor

Using two UPS's for Dual PSU DL380


I have a DL380 G3 with dual power supplies. If I plug each power supply in to a different UPS and as long as both PSUs are operating will the server draw power from each UPS if there is a power outage.

I ask this as I want to run equipment of the UPS which would normally require a large UPS (2200VA) but these seem to need to need special power points to be plugged in to. I was thinking if I got two 1000VA or 1500VA units which can use a standard power point and plugged some stuff in to each that this would overcome this issue. However if the server uses only one PSU at a time then there will not be load balancing over the two UPS for the server causing one UPS to run out of juice much quicker than the other.

Ivan Kuznetsov
Frequent Advisor

Re: Using two UPS's for Dual PSU DL380


Both PSUs are works in parallel if both power sources are available. It seems that power ratio between PSUs is not exactly 50/50. Typical measured value is about 60/40 (I don't know why)

But if one UPS will be turned off (e.g. somebody exidently pull the cord), another UPS takes all the server's power and can be overloaded

Regards, Ivan Kuznetsov