Linwood
New Member
- Joined
- Jan 5, 2022
- Messages
- 25
I changed an office UPS to use an AGM battery and had great luck. It had relatively small load and I just used the same size wire as was in the UPS, now about 2' each way vs 6".
I'm doing another for a network closet, it has a larger UPS partly because it also does a garage door, and the UPS is a sine wave.
I have a wiring question: This is a 1500va, 1000watt rated UPS. It uses two 12v batteries, call them 12.5 to make the math easy and it's about 60amps at full load (right? You use the before-power-factor number, not the 1000?).
It is wired with 10AWG stranded now. 60a seems high for #10 regardless of insulation type (and it's Chinese and unlabeled so not sure temp rating). It's a CP1500PFCLCDa if anyone is curious.
I went back and checked the first, it was also #10 but a single 12v system, 1000/600, so actually a bit worse now that I think about it.
Am I missing something here? Do UPS manufacturers just grossly under-size their wire? Except Cyberpower claims UL listing.
I was about to put #6 wire on it, but it looks kind of silly fastening #6 to #10 (and I haven't figured out how to open the case up to get to the PCB so I think I'm stuck fastening to their battery connectors).
Are they allowed to assume that the brief runtime at full load is brief enough that it can't actually do damage (rated runtime is 2.5 minutes at full load)?
I am not all that concerned -- the purpose of the UPS on the opener is for a one-time open with the power out (the garage has no other entrance, and inside is my generator). Make runtime is one cycle which is probably about 30-45 seconds, and at a guess 500 watts (with some starting surge) though I have not measured it.
But... why are the wires so tiny in a UPS? Is there an "out" for short duration (minutes) at way over typical ampacity?
Linwood
I'm doing another for a network closet, it has a larger UPS partly because it also does a garage door, and the UPS is a sine wave.
I have a wiring question: This is a 1500va, 1000watt rated UPS. It uses two 12v batteries, call them 12.5 to make the math easy and it's about 60amps at full load (right? You use the before-power-factor number, not the 1000?).
It is wired with 10AWG stranded now. 60a seems high for #10 regardless of insulation type (and it's Chinese and unlabeled so not sure temp rating). It's a CP1500PFCLCDa if anyone is curious.
I went back and checked the first, it was also #10 but a single 12v system, 1000/600, so actually a bit worse now that I think about it.
Am I missing something here? Do UPS manufacturers just grossly under-size their wire? Except Cyberpower claims UL listing.
I was about to put #6 wire on it, but it looks kind of silly fastening #6 to #10 (and I haven't figured out how to open the case up to get to the PCB so I think I'm stuck fastening to their battery connectors).
Are they allowed to assume that the brief runtime at full load is brief enough that it can't actually do damage (rated runtime is 2.5 minutes at full load)?
I am not all that concerned -- the purpose of the UPS on the opener is for a one-time open with the power out (the garage has no other entrance, and inside is my generator). Make runtime is one cycle which is probably about 30-45 seconds, and at a guess 500 watts (with some starting surge) though I have not measured it.
But... why are the wires so tiny in a UPS? Is there an "out" for short duration (minutes) at way over typical ampacity?
Linwood