Electronics > Beginners
KV/µA source, how do you measure the output?
<< < (4/4)
Leuven:

--- Quote from: Ian.M on June 29, 2019, 06:57:01 pm ---It depends on the length of the resistors as 50 in a row is going to be unreasonably long.  If you need 20mm each including joints that's a 1m long EHT probe!   Folding or zig-zagging the resistor chain makes it a *LOT* harder to manage the stray capacitances and stress on the insulation.  Personally I'd expect anything over 60cm long to be pretty unwieldy to use.  Fewer, higher value, higher voltage resistors would be preferable.   Of course you could put the resistor chain in an oil bath separate from the probe, but then you'll need >>100KV rated flexible EHT cable and there's a much greater risk to operator safety.

--- End quote ---

You're right, I can bring the number down some.
Leuven:

--- Quote from: joeqsmith on June 29, 2019, 08:23:16 pm ---Dang, that's an expensive repair bill.   I assume the end goal is to save money.   Do you think that the output degrades and you could have it serviced before a major failure happens?   Or maybe know when to order a new part before it totally fails?   IMO, it seems like you would just keep a spare part on hand (assuming it's for a business) to avoid down time or maybe find a more reliable gun.   

--- End quote ---

I'm pretty sure a replacement can be bought from a Chinese manufacturer at a much lower cost, that's one option to go about if it breaks. Some prefer to buy the brand name at full price, I suppose it all depends if you're making money with the equipment or not.

For my part, this is a home workshop and I bought the unit second hand. Before anything else, I want to confirm it's working ok. The manufacturer also recommends periodic checks, a problem (like a grounding issue) can creep up and lower your output voltage, and you wonder why you're not quite getting a good result with your wrapping. Maybe it's in the multiplier, maybe it's your setup. It's just good to have eyes on that output, for any eventuality.
joeqsmith:
Did the manufacture specify how to test it, what equipment was needed and such?  If not you could ask them what they recommend.  At least this way you are following their guidelines so if something is suspect, you can at least avoid having to explain your using something home made.  If I were a supplier and heard this, I would question the results no matter what.   

It may not be all that expensive.  Maybe something like a fencer (tester for electric fences).   
Leuven:

--- Quote from: joeqsmith on June 30, 2019, 03:39:01 am ---Did the manufacture specify how to test it, what equipment was needed and such?  If not you could ask them what they recommend.  At least this way you are following their guidelines so if something is suspect, you can at least avoid having to explain your using something home made.  If I were a supplier and heard this, I would question the results no matter what.   

It may not be all that expensive.  Maybe something like a fencer (tester for electric fences).   

--- End quote ---

They do sell a test kit, which is basically a DMM and a fancy 100G high voltage probe. For megabucks, I'm sure, but even if it were cheap - I really don't see any reason why their HV probe would be any better than a good home-made HV probe.

They also mention about checking the multiplier's resistance with a megger. I couldn't find any more info about that, but you can't beat an actual voltage test.

http://emanuals.nordson.com/finishing/files/powder/107004e02.pdf
Navigation
Message Index
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod