Ups

[Les Fischer]

I have 400a 480v 3 phase load that will be supplied thru a UPS system. The primary input and output are the same voltage .How do I calulate the load comsumed by the UPS system alone ???


Les:-?

 

[chris kennedy]

All this info is in the manual that comes with it. Can you read German?

 

[brian john]

Several factors will play into this issue, volts, amps, power factor, (KVA/KW)percentage of load, efficiency of the unit, typically a fully loaded UPS is more efficient that a lightly loaded UPS.

UPS manuals are at best limited in useful information IMO.

 

[chris kennedy]

UPS manuals are at best limited in useful information IMO.

Hence the "can you speak German" comment. But it was easy to get the info I needed. These people spend alot of money on these systems. Customer service has been outstanding.

 

[brian john]

I have found customer service to be a mixed bag of help. Like most things it depends on who you get. Had one tech I had to explain to him how the Aux I/O Bypass cabinet was to be wired, other tech are a wealth of knowledge.

I now get the German reference (bit slow here).

 

[chris kennedy]

I now get the German reference (bit slow here).

Brian John, I have some friends in India if you would like to talk to them.

 

[robbietan]

I have 400a 480v 3 phase load that will be supplied thru a UPS system. The primary input and output are the same voltage .How do I calulate the load comsumed by the UPS system alone ???


Les:-?

depends on what UPS you have. If its a standby UPS, probably negligible as these consume power only when its battery was used. If its an online type, a slight load may be added, as losses from the AC to DC conversion

 

[dbuckley]

I'll assume that a UPS of that size is an online UPS, for which there is usually a full load efficiency supplied in the manual, and the power consumed by the UPS is the few percent between the efficiency and 100%. And its usually a VA percent. So if you have a 100KVA UPS that is 96% efficient, then do (load / efficiency) * 100 to get total load, so (100KVA / 96) * 100 = 104.16KVA.

On top of that you need the recharge load of the UPS, and for that you will need the manual.