I am trying to study the operation of a single plate Induction Hob.
I wanted to use an oscilloscope to measure some of the low voltage digital signals on the microcontroller inside. So I attached the ground lead of the 'scope to a pin labelled 'GND'.
But when I powered up the hob, the fuse inside exploded. I guessed that this is because the GND line is actually bouncing up and down with the AC supply.
Is it possible to use a 'scope to measure signals inside a mains device like this without something exploding or risking damage to the oscilloscope?
I don't have a schematic for this appliance, but it's likely to be pretty similar to most other induction cookers, like this one:
In the top left you can see the AC come in, then there's a bridge rectifier with the negative terminal defined as ground.