Is this transformer good?

[ben7]

Hello, I just got an old 'BEST' brand UPS today, to take apart or repair. Interesting unit, with a large (!) ferro-resonant transformer.

Person who I got it from said it died from a thunderstorm/surge.

All fuses are good, but one of the small transformers for powering the logic circuits seems to be fried.

The question I have is this: The primary measures about 460Ω. Is this bad?

The other small transformer has a primary resistance of about 100Ω, which seems good. Haven't plugged it in yet, and sorry, no pics.

The transformers are both PCB mount, and both are about 1.5'' by 2''. The one in question is slightly smaller. Both are made by 'CRAMER'.

BTW, some wacko solder-blobbed over the vent of the big oil filled capacitor. It isn't bulged, but, ugh... lol And you don't want to know how dusty and filthy that thing was! XD

 

[JoeJester]

**broken link removed**

Look through the catalog and see if you find your transformer

 

[ben7]

Yeah, I did, no luck...

 

[JoeJester]

What is the model number of your "cramer" transformer?

Can you post a photograph, a clear photograph, of your transformer, showing the part numbers?

What is the model number of your "Best" UPS?

 

[johansen]

yeah, uh that solder blob over the vent hole is to keep the oil in...


2800 turns of 40 gauge wire around a core on the order of 10 mm by 15mm is on the order of 1000 ohms.

so your 460 ohm primary is about right for a transformer that small.

 

[ben7]

Ok, I got around today to pull out the transformer, the two primates read about 460 ohms and 1200 ohms. Applying 120vac to either one gives 12v on the output, so I think all is good here...