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Electronics => Repair => Topic started by: Jecarroll7 on January 28, 2017, 08:21:31 pm

Title: Sencore LC102 Dielectric Absorption Calibration
Post by: Jecarroll7 on January 28, 2017, 08:21:31 pm
I have a Sencore LC102 that I believe needs repair and calibration.

Relays seem to work okay, don’t get any errors and Capacitor Values are in the park but not perfect.

However I’ve have a problem with Dielectric Absorption, ESR and sometimes Leakage tests

Visually, everything looks okay inside.  I have a relatively new power supply and lead set both purchased from Sencore a few years ago.

Following Sencore’s calibration instructions

Power Supply:
-   On step 7. The .975vdc bounced around a bit +-0.040 or so
-   Same for step 9.
Capacitance Calibration:
-   On step 3. Adjusting for a 1500pF value, R55 bottomed out at 1565pF (pretty sure its not the cap as I have two different model DVMs with capacitance value capability and both of those were very close to the 1500)  I'm guessing some of the components inside the LC102 changed value over time?  Or its part of a larger conspiracy?
-   Step 8 is where I ran into problems, I did hear relays kick in, but looking for 417mA on my DVM I got no DVM reading of any mA, turning the adjustment pot R80 in either direction had no effect.

That’s where I stopped.  Wondering if anyone had a suggestion?
Title: Re: Sencore LC102 Dielectric Absorption Calibration
Post by: ruairi on January 29, 2017, 06:40:38 am
It might be obvious but are you sure that your probes are plugged into the correct socket on your multimeter to measure current?