Quote: Originally Posted by cvi
Might be, but what about the efficiency and weight of this setup? Search for "tank circuit" to find another way to do this without having a "DC-AC converter -> iron transformer -> UPS -> AC-DC converter(psu) " setup. There are better ways.
He's not trying to make a tank circuit, he's trying to make a shutdown controller. Completely different thing. Still a wrongheaded way to do it, though.
Quote: Originally Posted by alik
The main reason I want to use UPS is to gracefully shutdown PC when my engine is off. Unlike many auto-shutdown devices that use serial port my UPS uses USB. My setup doesn't have any spare serial ports, that is why I am thinking about UPS.
Most (all?) of the shutdown controllers I've seen do not use the serial port, they connect to the ATX switch headers on the motherboard, as this is what that was designed for. Where did you find one that uses the serial port?
You would be much better off getting an ITPS and bypassing the regulator to use it as just a shutdown controller.
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