I recently acquired a transformer for which I can't locate a data sheet. I would like to test it but at his point I am unsure of the primaries. The transformer has no serial number but here is a picture of the specs:
I measure the resistance in the primaries and find that if I assume that brown is the common, orange has 2 ohm and red has 4. I would assume that more copper has more resistance which would make the red the 230V lead and the orange the 115V lead. Am I far off here?
I suppose if I have that much right, it's safe to move forward with the bulb test. I've searched the forums a bit but I haven't found anything suggesting what wattage should be used to do that. Any advice?
An externally hosted image should be here but it was not working when we last tested it.
I measure the resistance in the primaries and find that if I assume that brown is the common, orange has 2 ohm and red has 4. I would assume that more copper has more resistance which would make the red the 230V lead and the orange the 115V lead. Am I far off here?
I suppose if I have that much right, it's safe to move forward with the bulb test. I've searched the forums a bit but I haven't found anything suggesting what wattage should be used to do that. Any advice?
You are probably right about the primary.
For a lamp limiter any normal domestic bulb power would do, as all you are doing is covering for a shorted turn.
The total transformer VA rating can be estimated from size and weight, so look at catalogues. Bear in mind that the two secondaries may have quite different ratings e.g. 36V at a few amps for power amp, and 20.8V at, say, 100mA for preamp. Secondary resistance measurements will help.
Yes, I would guess 100VA too.
For a lamp limiter any normal domestic bulb power would do, as all you are doing is covering for a shorted turn.
The total transformer VA rating can be estimated from size and weight, so look at catalogues. Bear in mind that the two secondaries may have quite different ratings e.g. 36V at a few amps for power amp, and 20.8V at, say, 100mA for preamp. Secondary resistance measurements will help.
Yes, I would guess 100VA too.
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I hooked it all up today with the light bulb in series. I wired the primaries according to what I learned from previous testing. When I flipped the switch, no light came on so that went well. I tested the secondaries and they seem fine as well.
Thank you all for your input. You were very helpful.
Thank you all for your input. You were very helpful.
An externally hosted image should be here but it was not working when we last tested it.
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