Re: capacitor leakage go/no-go test
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LOn Wed, 30 Nov 2022 at 02:29, saipan59 (Pete) <saipan1959@...> wrote: I have various piles of old caps, many NOS, etc. I'm interested in doing a simple go/no-go type of test for leakage. Agilent made a couple of high resistance meters.? The 4349A has 1, 2 or 4 channels, depending upon the options installed, but needs an external power supply up to 5 kV. The 4339B is a capable of measuring higher resistances, and has a built in 1 kV power supply. It would be worth looking at the manuals for them, as they cover capacitor testing. They are capable of measuring very low currents - I think down to aA, which I doubt would be necessary for most capacitors.? I was a bit annoyed that I sent two 4339Bs to Keysight UK. Both were very slightly out of specification on the 10 nA range, but neither could be adjusted, despite all adjustments are electronic. ???? There OPA128 IC is designed for electrometers. There used to be some electometers on a PCB from China on eBay, but I can¡¯t find any now.? A fairly standard way of reforming old electrolytic caps is to gradually increase the voltage using a very high resistance, so low current. Personally I just replace them.?
Dave? Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Dr. David Kirkby, Kirkby Microwave Ltd