Author Topic: Keithley 2100: How does one identify a burnt SMD resistor without service manual  (Read 11040 times)

0 Members and 2 Guests are viewing this topic.

Offline bendzo

  • Contributor
  • Posts: 6
  • Country: sk
Hi,
thank you! It's actually mostly your merit  :-+ , thanks again Kleinstein!
I bought this faulty meter to look inside and learn something by hands-on experience, and it was a big success!
And as a bonus meter seems to work fine after repair, I will try to roughly test it's precision, but I don't really have any suitable references at this moment.

There is only one last annoying/suspicious thing, meter has a big(?) offset from zero, it's reading 0.18mV with leads shorted, the same for amps, 0.18mA for 1A and 3A range, 0.035mA for lower amps ranges (gain 0.2?), is it a fault? Is there any way how to "fix" this offset (beside "NULL" button of course ;) ) ?
Thank you!
 

Offline Kleinstein

  • Super Contributor
  • ***
  • Posts: 6340
  • Country: de
The meter likely has a software function to compensate for input amplifier offset. So a kind of null function, but more permanent.

If this function was used by the previous owner with the bad higher bias current this would likely also result in extra offset.

So checking the offset calibration should be the first step.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf