More electrical shenanigans - any thoughts?

[Noodle Legs]

Maybe worth testing the offending circuit to see the earth leakage figure.

As well as an ins res test. Low insulation resistance can also give way to rising earth leakage currents.

 

[Reynard]

You guys have lost me.

But the power is still on.

 

[Solocle]

It reminds me, in my day when diagnosing microwave oven problems. I would regularly tap into the magnatrons HV circuit to test current draw whilst running the oven and also HV output. AlI done using an analogue AVO meter. Fluke digital meters back then weren't able to measure the peak HV
-too high.

Some years later we had a warranty claim for our home microwave. The technician would replace a suspect part, without any circuit testing, put the case back on and test.

I asked him why he didn't circuit test to diagnose the problem instead of parts swapping. He said they weren't allowed to test live equipment.

With good reason. The internals of a microwave oven are about the scariest thing in an average home.

I had a fiddle with a scavenged microwave transformer this week, but I took significant precautions. Mainly a 2 metre social distance.

Here's it generating some nice big sparks when I turned it off - the flyback of the magnetic field collapsing. The spark gap was obviously too big for the >2000V output to jump.

And then I moved the ends closer together.