The model is 430-7101(3) and is from an APC UPS and there are 2 of these that run in series - Each has a 4 wire connection on the main board and the terminals on the mainboard look to be in parallel.
I did a continuity test on the 4 wires and wire 1 & 3 and 2 & 4 signal as a single wire. Wire 2 (black) has a 15A 125v inline fuse and all wires are 16awg.
Since this is a UPS, IDK which is considered primary as if it is being battery fed, then the larger gauge would be primary and step up the voltage.? But I didn't think DC could be stepped up like this, Could that be why there are 2 sets of wires on the high voltage side?
I'm trying to find out what the output voltage is of the transformer and wanted to know what wires to use to test 120 AC. I was thinking that using 1 & 2 as + and 3 & 4 as - , but wanted t check if that would be correct (fusing concerned me)
Actually after thinking about it, I think the 2 sets are for 120 and 240. When 120 is detected connector 2 and 3 are "shorted" to make a longer wire. Does that seem possible?


I did a continuity test on the 4 wires and wire 1 & 3 and 2 & 4 signal as a single wire. Wire 2 (black) has a 15A 125v inline fuse and all wires are 16awg.
Since this is a UPS, IDK which is considered primary as if it is being battery fed, then the larger gauge would be primary and step up the voltage.? But I didn't think DC could be stepped up like this, Could that be why there are 2 sets of wires on the high voltage side?
I'm trying to find out what the output voltage is of the transformer and wanted to know what wires to use to test 120 AC. I was thinking that using 1 & 2 as + and 3 & 4 as - , but wanted t check if that would be correct (fusing concerned me)
Actually after thinking about it, I think the 2 sets are for 120 and 240. When 120 is detected connector 2 and 3 are "shorted" to make a longer wire. Does that seem possible?


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