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Electronics => Repair => Topic started by: Eldi4 on April 03, 2019, 04:48:44 am

Title: Help to identify the value of resistor
Post by: Eldi4 on April 03, 2019, 04:48:44 am
Did anyone know what is the value of this resistor, the color coding does'nt make any sense for me,  it was found on Delta Electronic DPS-220UB power supply, and the resistor is open-circuited.

Red-Red-Gold-Gold-Black?, what?
Title: Re: Help to identify the value of resistor
Post by: Pete66 on April 03, 2019, 05:11:16 am
I had a similar situation before after a week of trying to figure it out it turned out that the black band was only there to indicate the end of the resistor.  So based on that I would guess its a 4 band resistor Red-Red-Gold-Gold and the last black band is only there to show where it ends.  I could be wrong though
Title: Re: Help to identify the value of resistor
Post by: Eldi4 on April 03, 2019, 05:23:25 am
 Well that is pretty reasonable,  so it was 2.2 Ohm probably,
 what is your resistor looked like, where is it placed?
Title: Re: Help to identify the value of resistor
Post by: digsys on April 03, 2019, 05:42:36 am
Not that it looks anything like the ones I've used, but 5 band values include tolerance (not black though), and 6 band ones include tempco - 250ppm
But that ones does not look like a precision one .. can you measure it?
Title: Re: Help to identify the value of resistor
Post by: Pete66 on April 03, 2019, 05:46:10 am
I don't remember I think it may have been a CFL or LED circuit.   I do remember spending a while trying to figure it out and it turned out that the fifth black band meant it was a non inductive resistor.
So I treated it as a four band resistor and it worked out. 

You could try to find a forum where someone that has that same power supply and ask them to measure it for you.
Title: Re: Help to identify the value of resistor
Post by: Pete66 on April 03, 2019, 05:50:42 am
I got bored and did a quick search on here and someone had the exact same question a couple of years ago.   :o
I think this will help you out.
https://www.eevblog.com/forum/beginners/resistor-confusion/ (https://www.eevblog.com/forum/beginners/resistor-confusion/)


Title: Re: Help to identify the value of resistor
Post by: Eldi4 on April 03, 2019, 05:56:12 am
I got bored and did a quick search on here and someone had the exact same question a couple of years ago.   :o
I think this will help you out.
https://www.eevblog.com/forum/beginners/resistor-confusion/ (https://www.eevblog.com/forum/beginners/resistor-confusion/)




Well, i think it's clear, thank you very much
Title: Re: Help to identify the value of resistor
Post by: Gyro on April 03, 2019, 09:09:54 am
Note the comments about it being fusible - any resistor that measures open circuit, with so little apparent damage, is almost certainly a fusible type. Replace with the same for continued safety.

You also need to find out why it fused, otherwise the new one will almost certainly suffer the same fate.
Title: Re: Help to identify the value of resistor
Post by: David Hess on April 03, 2019, 10:23:54 pm
Red, red, gold, and gold is 2.2 ohms and 5%.  I assume the black band indicates a special feature like fusible or flame proof.