How to Test a Transformer with a Multimeter

[@JustinVodden]

Don't you need to give an auto ranging meter a moment to adjust and give a reading?

[@danek_hren]

Yes, he's doing аss-ly

[@thomasfink2385]

Right. I'm out

[@Coconutpelau]

So we see meter readings but what do they mean?... Going elsewhere for explanations that I can follow and learn.

[@d614gakadoug9]

Alligator clips are much better than simple probes for this type of testing. There is often residual flux on the transformer leads. Alligator clips will "bite through" the residue whereas probes may not. The fact that the resistance shown on the meter in the video frequently varied a great deal suggests there is a problem like this. Transformer windings rarely fail open-circuit, however some small transformers have an non-resetting over-temperature device in series with a winding and it can go open-circuit. Winding resistance measurement will almost never detect a shorted turn. A shorted turn happens due to damage or breakdown of the insulation of a winding. A single shorted turn on a transformer intended for 50 or 60 Hz use will make almost no difference in the measured resistance. You'd have to have a known-good transformer for comparison and even then it wouldn't be conclusive. A single shorted turn will make a transformer useless.

[@gregebert5544]

Touching the leads makes no significant impact on the reading (typically a few ohms), as fingers are generally several hundred K-ohms. BUT.....as you will find out, when you touch the leads you can get shocked from the inductive kick-back.

[@jbsmith86]

I thought OL means open line???

[@ElectroUniversity]

I have a video that explains what OL means at kzbin.info/www/bejne/r57ZqquijMl4mc0

[@STRANGE_hour]

You’re not explaining anything - lol

[@STRANGE_hour]

I mean you’re literally just translating the meter readings into words - we know it has resistance we can see the meter what we don’t know is why certain readings make for a bad transformer lol wth is going on here you need to watch a KZbin video on how to make an instructional KZbin video my friend