One other trick to check a transformer is to measure the resistance of the
secondary winding. Then using a variac, connect an ammeter across the secondary,
and wind up the primary volts until the secondary current is the desired value.
Run it until the temperature has stabilised, remove voltages and remeasure the
secondary winding resistance again. From the standard formula, you can work out
the winding temperature, and decide if that is within accptable limits.
If the secondary winding resistance is too high, you can stop at that stage....
73
Peter G3RZP
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