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Electronics => Repair => Topic started by: Aglovale on April 06, 2019, 07:21:03 pm

Title: Identifying inductors and testing link switch for condenser dryer pcb.
Post by: Aglovale on April 06, 2019, 07:21:03 pm
Hi all. I am trying to repair my condenser dryer -It won't power on- and I need some help if possible. I have been testing caps, diodes and relays without any faults found as of yet. However, while I was testing inductors I noticed odd readings from 3 inductors in particular. According to the colour bands on  3 inductors in picture 1, (only 2 are in picture 1 as the other was de-soldered for testing. however, the de-soldered one is identical to the blue circled inductor - even in readings) the ohms seems to be way off. According to Digi-key web site, the blue circled inductor (Yellow, violet, red and silver band) should be 4700uf and I have a reading of approx 17ohms. The red circled inductor (brown, black, black and silver band) should be 10uf and I'm getting a reading of approx 0.6ohms; all 3 inductors are approx 10x4 mm in size.
I found it strange that all these inductors were faulty. However, after some research it seems that the link switch (Picture 2, circled in purple) commonly fails on these boards and can damage resistors (maybe also inductors?) in in the process - from what I have read. The other option of course is that I'm reading the bands incorrectly.
Can someone help me identify the resistors and maybe tell me if there is anyway I can test if the link switch is working correctly (as I am not familiar with them).
Thank you.
Title: Re: Identifying resistors and testing link switch for condenser dryer pcb.
Post by: coromonadalix on April 06, 2019, 07:48:13 pm
they are inductances not resistors, and the hint is L2 and L3 on the pc board

Inductor Colour Codes
http://www.learnabout-electronics.org/ac_theory/inductors04.php (http://www.learnabout-electronics.org/ac_theory/inductors04.php)
Title: Re: Identifying resistors and testing link switch for condenser dryer pcb.
Post by: Aglovale on April 06, 2019, 07:58:02 pm
Quote from: coromonadalix on April 06, 2019, 07:48:13 pm
they are inductances not resistors, and the hint is L2 and L3 on the pc board

Inductor Colour Codes
http://www.learnabout-electronics.org/ac_theory/inductors04.php (http://www.learnabout-electronics.org/ac_theory/inductors04.php)

Thank you so much, I am fairly new to electronics - as my ignorance indicates - I've edited title and description to reflect on your information.
Title: Re: Identifying inductors and testing link switch for condenser dryer pcb.
Post by: Aglovale on April 06, 2019, 08:30:02 pm
Ho do I test inductors ?
Title: Re: Identifying inductors and testing link switch for condenser dryer pcb.
Post by: coromonadalix on April 06, 2019, 09:02:16 pm
Well the cheap way is : to test them as a short,  if they read something in ohms they may be good since you dont have "infinite / open" value

The official way is to test them with an lcr meter