Electronics > Projects, Designs, and Technical Stuff
9kV CW multiplier potting process
<< < (3/3)
floobydust:
I add PC board holes and slots to ensure the potting compound flows in nooks and under parts. It also helps the compound bond to the board and not peel off a side, as a big slab.
I get most air bubbles added during mixing and pouring.

For HV multipliers, an output resistor is added to limit diode current if the load can ever arc.
I run the boards in air in total darkness to see where the corona hot spots are, if the PCB layout is not so great you can see the glow. Sometimes a sharp edge or spacing is missed.

Some HV rectifier diodes are sized to be potted i.e 2CL71MT is SMA yet rated to 8kV and I estimate ~2.5mm gap between pads. You wouldn't use that in air.
ahbushnell:

--- Quote from: MasterTech on June 11, 2020, 12:42:15 am ---Just two things, I’m surprised that the pcb does not have any cut slots, below diodes and caps, moreover when diodes are not placed in a triangle shape. Also, usually hv pcbs to be potted do not have any soldermask, just bare pcb.
The filling process seems ok for the voltages your dealing with

--- End quote ---
I agree.  We always make slots under HV components. 
doktor pyta:
Thank you for valuable feedback !
Navigation
Message Index
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod