THCAD selection including ohmic sensing

Damn! Please do not touch those 2 pins while the plasma is on!
I really hope they bothered to put some resistors inside of that thing.
In that case a THCAD300 should do just fine and save you a lot of work.
Please also use proper isolation for that connector and make sure those two wires are not pinched or crimped somewhere.

calvin.d wrote: The back of the machine shows 1:1 as the ratio so I believe I need the 300v option, picture added

for the ohmic sensing side of the question, it seems like going with 5v and just adding a small 5v power supply to the system is the easiest option. Compared to getting a 10v supply or dividing down the 24v power the system to less then 10v

Thank You
C

Actually you want a higher sensing voltage, 24V or even 48V is suggested
Note that this needs to be an independent floating supply (no connections to anything else in the system)

Can you measure the resistance from the electrodes at the front of the machine and those pins on the back of your machine?
I would expect that there is around 100k ohm resistance if its like any other machine that has raw voltage output so you don't kill yourself.

I think you should use a THCAD-10 so that you can account for this resistance. eg. follow the example in the THCAD-10 manual and then deduct the resistance (200 k Ohms?) from the calculated values.

Also using a THCAD-10/5 for ohmic sensing will require a component I have written but its not yet published.

rodw wrote: Also using a THCAD-10/5 for ohmic sensing will require a component I have written but its not yet published.

Oh, you've been holding on us !

rodw wrote: Also using a THCAD-10/5 for ohmic sensing will require a component I have written but its not yet published.

What? What does the component do? I bought two of the thcad-10 to use for this.

Are you going to release the component? Did I ask what the component does?

bevins wrote: Did I ask what the component does?

Yes you did.