Dear Anthony, Keep in mind that the UPS typically is not operating at full power.
The Sealed Lead Acid Cells (SLAC) are very likely capable of burning out their own feed wires, but that would be in a serious high current short circuit situation. On Fri, Dec 19, 2025 at 4:00 PM Anthony Carrico < [email protected]> wrote: > The Tripplite 1500LCDT has a 1500VA (900W) output rating. It is 120V @ > 12A. I guess they round 1440 up to 1500, which seems like bad math, but > anyway... > > Inside there are two 12V SLA batteries. I've replaced these things in > the past, but today I was looking at the wire, and noticed that it is > 12AWG. > > As far as I know, 12AWG wire is good for 20-30Amp depending on > temperature, and two 12v batteries in series is 24V. > > 24V*20A is 480VA. > > 24V*30A is 720VA. > > 480 to 720 minus inverter losses are much less than 1500, so what gives? > > The batteries are capable of AMPs well in excess of 40 AMPS, but not for long. > Is the 12AWG wire OK because its length is short? Or do I not understand > the UPS's power rating? > > Notice that the spade lugs to the battery are sized for the 12AWG Also notice the Underwriters Laboratories cert. You pays your money, you take your chances... Love and Seasons Greetings Flint
