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Trying To ID This Transformer

Posted by benesesso (My Page) on
Thu, Feb 28, 13 at 16:21

Found this new xformer in a box--unknown source. Too many wires for my simple brain.

I need 24v from 120v.

Measured the resistance between the two "primary?" black/white wires, 6.3 ohms. That's like ~20amps at 120v!

Hopefully the input resistance/impedance goes way up when it's energized.

Google search of the numbers was no help. Any ideas?

Follow-Up Postings:

RE: Trying To ID This Transformer

Just remembered, it came from an APS battery backup power supply for a computer. It was fed from a pair of 6v sealed batteries.

OK, 6V (I think the batteries were in parallel) up to 120v. Looks like I'm out of luck here.

RE: Trying To ID This Transformer

When energized by AC power, the inductive reactance serves to limit the primary current exactly as higher resistance would do.

RE: Trying To ID This Transformer

If this was used for a UPS, then most likely the black & white wires are the Secondary.

The two 3-wire pairs are the Primaries - the same gauge primary/secondary was probably the AC line input (with surge suppression, RFI filtering and relay switching) in normal operation.

The heavier gauge wires were probably from the inverter output and used the transformer to produce the stepped up voltage when in UPS mode.

RE: Trying To ID This Transformer

Thanks. Guess I'll have to pop ~$10 for a 24v eBone special.

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