UPS branch circuit

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Ears3311

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Question about designing the branch circuit for a UPS that is capable of a 3000VA/2250W output. I calculate that the UPS will draw 25A (3000VA/120V). To size the conductors and breaker, I multiply the 25A by 125% because it is a continuous load. This results in a 31.25A load. The next size breaker is 35A. However, the input connection for the UPS is a L5-30R, which is only rated for 30A.

Is the 30A receptacle protected by the 35A breaker? If not, how do I resolve this issue.
 
That looks to me as though it pulls 2250W continuously or 3000 peak, does that seem right? In that case, the 30A breaker and wiring should be correct, I would think.
 
If the UPS comes with a 30 amp plug from the manufacturer, size the branch circuit accordingly.
 
But the manufacturer says that it is capable of 3000VA output. This equates to 25A, which when multiplied by 125% puts you over a 30A breaker.
 
What size branch circuit does the manufacturer recommend? It would seem rather strange that they would install a cord and plug that could not carry the load.
 
http://www.apcc.com/resource/include/techspec_index.cfm?base_sku=SUA2200RM2U&total_watts=50

The manufacturer does not recommend a branch circuit size, unless you can find it.
 
The manufacturer did specify the branch circuit requirements by installing a L5-30P on the unit (UL listed as designed).
 
...If it looks like a duck...

...If it looks like a duck...

I agree with George 3000VA is peak only... 2250VA is used for the continuous calc. Also agree's with the L-5-30P.
 
wanderer20001us said:
The manufacturer did specify the branch circuit requirements by installing a L5-30P on the unit (UL listed as designed).
Click to expand...

I agree.

Not only did the manufacturer install a L5-30P on this for a reason, it was UL listed to be used with a 30 amp supply.

Install a L5-30R on a 30 amp branch circuit and be done with it. :)
 
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