i have a few old power transformers i have pulled from radio receivers and solid state amps. i would like to re purpose these for a power supply. how can i test them to find the voltage rating?
Thanks
Thanks
look for obvious defects like burned smell, charred insulations...etc..
did you mark which leads are primary and the voltage they are set to?
did you mark which leads are primary and the voltage they are set to?
Use a lamp limiter and a meter. It helps considerably if you know for certain which is the primary.
The higher resistance windings will normally be the primaries, unless you are pulling from old valve amps.
yes. i know the primary and secondary, i just have no clue what the voltage rating for the secondary is if that makes sense.
thanks
dan
thanks
dan
The general way to find out the voltage ratings is to connect the transformer to your mains (with the light bulb tester in between) then using your DMM to measure the voltages of the secondary windings .....
To find the Va rating of the transformer is a bit more complex , but luckily it is usually displayed on the back of the equipment you salvaged it from ... for instance I recently salvaged a transformer from an old sony 5.1 receiver and on the back of the receiver it stated the 300w 420vA ....
Cheers
To find the Va rating of the transformer is a bit more complex , but luckily it is usually displayed on the back of the equipment you salvaged it from ... for instance I recently salvaged a transformer from an old sony 5.1 receiver and on the back of the receiver it stated the 300w 420vA ....
Cheers
If you have a DMM with a low voltage AC range. You could safely use an AC output wall-wart supply for preliminary voltage testing. In the US a wall-wart with a 12V AC output connected to the transformer's input would give you 1/10 of the true output voltage.
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