How to measure charging of Cockcroft Walton Multipliers?

shrinky

How do you measure the voltage of a cockcroft walton multiplier over time to observe the charging behavior? Does measuring with oscilloscopes discharge the capacitor hence you cant observe the charging or not?

NascentOxygen

The oscilloscope doesn't impose much loading on the circuit. You are wanting to observe the actual pumping up? That will be a short term transitory waveform. Using a CRO with differential inputs might be handy, if you wish to observe all waveforms around the circuit.

shrinky

Yeah. Ideally I'd like to see the oscillation with amplitude offset increasing as time goes on.

Right now I have a simple half wave multi stage multiplier set up. I can measure the rectification part, so the sine wave only goes to the positive and not negative, but I dont see the amplitude increase so that the dc offset is always zero essentially.

It could be my driving frequency isnt correct perhaps?

Rhetorical I guess but is it better to measure the voltage across the capacitor at the highest stage or measure the potential relative to ground.

NascentOxygen

Well, it's a transient, so unless you have a storage CRO or a synchronised camera, you won't see it.

Are you saying it's not working?

It shouldn't matter.

Can you post your circuit schematic?

Unless your driving source is floating, you can't connect the CRO across any ungrounded element.