MESA THCAD-5 Quick Questions

Hello everyone, 
First of all this place here has been a huge help for me troubleshooting my build even though i have only been a Lurker so far (had some watchdog latency problems ).  
But now i am at the HV side of things so i would rather ask some questions instead of burning my THCAD.

I am currently building a 2.5m x 1.5m Plasma Table With a MESA 7I96s controller board and a Cebora PlasmaProf 52 HF machine and a THCAD-5.
I have identified the rectifier outputs of the machine and i would like to ask some questions about the Input dividers.
The Manual says i would need a total of 10MOhms to reach the 500VDC with the required 50 uA of current.
I have read posts here saying i have to attach 5 Mohms to each pin so inut + and input - of the THCAD to reach my 49:1 conversion.
But other posts such as this one  say that one 2.4 Mohm resistor on the negative lead would be enough for the THCAD-2 to reach the 250 Volts.
so which way should i wire up my THCAD-5 in order to get my 49:1 voltage division ? 

I would be glad if someone could clarify the situation to someone like me who has just started with his build and has no prior experience whatsoever.

Greetings 

 

A THCAD-5 is 50 uA full scale and has a 100K input resistance.
so for 250V full scale you would use a series resistance of
250V/50uA -100K = 4.9M

Hi,
first of all thanks for the quick reply i really appreciate the help.
So 4.9M high voltage and wattage resistor on the negative lead of the THCAD ?


Greetings
 

Yes