Re: UPS for modified sine wave system?
Unless I've gone completely senile in the past two weeks (possible) the Trace SW4048 is a sine wave inverter. It should have no trouble running a UPS.
So perhaps that is not the problem you're experiencing. The SW series is no longer made and support/repair can be difficult to attain (as often lamented on this forum - they were good inverters).
The logical question would be; if you've got a battery-powered, true sine wave invert, what do you need a UPS for? Could you give more detail as to the current set-up and what further you're trying to get it to do?
1220 Watts of PV, OB MX60, 232 Amp hrs, OB 3524, Honda eu2000.
Ohm's Law: Amps = Volts / Ohms
Power Formula: Watts = Volts * Amps