Storage Battery Rooms

[Bob Clukey]

Could someone describe the requirements for overcurrent protection for UPS systems or storage battery rooms?

 

[dwellselectric]

Could someone describe the requirements for overcurrent protection for UPS systems or storage battery rooms?

We just did one but to be honest I dont understand your question. Requirements for overcurrent protection or for the room the UPS is in?

 

[petersonra]

not a whole lot different than any other branch circuit unless you are talking about the batteries.

 

[dereckbc]

Not sure I understand either and I design the things. If you are talking from the batteries there is no requirement.

 

[don_resqcapt19]

Not sure I understand either and I design the things. If you are talking from the batteries there is no requirement.

Dereck,
Why doesn't 240.21 apply? It appears that it does, as there is a subsection, 240.21(H), that covers the location if the OCPD.

 

[dereckbc]

Because a UPS is a listed system equipment and not part of the premise wiring system therefore not under NEC requirements.

 

[don_resqcapt19]

Because a UPS is a listed system equipment and not part of the premise wiring system therefore not under NEC requirements.

Ok, I understand that, but the original post also talked about a battery room.

 

[ron]

Dereck,
If the batteries are within the UPS, then I consider whatever is assembled by the UPS manufacturer to be listed as an assembly.
If the batteries are rack mounted and there is a free standing battery OCPD/disconnect, I apply the same rules like feeder OCPD.