Author Topic: Uni-t UT61E autorange problem?  (Read 417 times)

0 Members and 1 Guest are viewing this topic.

Offline thanosbiTopic starter

  • Newbie
  • Posts: 3
  • Country: gr
Uni-t UT61E autorange problem?
« on: December 02, 2024, 09:41:09 pm »
Hello everyone,
After a few years of use i noticed my 61e doesn't autorange in DC if the polarity is reversed,it just displays -OL. If i select manually the range displays the value correctly. I have already changed the battery and cleaned the selector switch pads.The calibration is spot on. I also noticed that AC amperes gives around 0.056A without being connected. Does anyone faced something similar?. Where should i begin looking? Thanks.
 

Offline coromonadalix

  • Super Contributor
  • ***
  • Posts: 7001
  • Country: ca
Re: Uni-t UT61E autorange problem?
« Reply #1 on: December 03, 2024, 03:00:54 am »
ut 61e schematics
 

Offline thanosbiTopic starter

  • Newbie
  • Posts: 3
  • Country: gr
Re: Uni-t UT61E autorange problem?
« Reply #2 on: December 03, 2024, 07:35:34 am »
Thank you! i already have this
 

Offline thanosbiTopic starter

  • Newbie
  • Posts: 3
  • Country: gr
Re: Uni-t UT61E autorange problem?
« Reply #3 on: December 03, 2024, 08:12:40 am »
Update. I think i fix it looks ok so far.
C36 tantalum was dead.The readings suggested something like a diode issue,hard to imagine that this tantalum transformed into one! Replaced both decoupling caps around the LDO with 22uf smd electr.
Abnormal readings fixed by changing c33,which after removing revealed electrolyte? leak
Dont trust capacitors especially tantalums.Basicaly these multimeters seems to be made with awful quality parts!
 

Offline coromonadalix

  • Super Contributor
  • ***
  • Posts: 7001
  • Country: ca
Re: Uni-t UT61E autorange problem?
« Reply #4 on: December 04, 2024, 11:02:11 am »
 :-+
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf