Author Topic: What is this part and resistor value  (Read 468 times)

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Offline Peter TryndochTopic starter

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What is this part and resistor value
« on: July 17, 2024, 09:15:12 am »
What is this component that looks like a diode and is labeled "TRSB1" ?
My colour vision is not the best. Is the value of this shunt resistor 4R9?
Hopefully the image will get attached to this post Ok.
Altronics did not have a 4R9 so I went with a 5R6 5W

Some history - if you're interested:
This is the low voltage supply for an overly complicated clothes dryer.
The shunt resistor failed. I replaced it with the 5R6 and then the control chip let out the magic smoke.
I measured the DC resistance of the primary as 0R2.
I rewound the transformer and now the primary measures 15R. Much better.
Now waiting on delivery of replacement LNK364GN
 

Offline fzabkar

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Re: What is this part and resistor value
« Reply #1 on: July 17, 2024, 03:43:22 pm »
TRSB1 is a TVS diode (Transorb). The two numbers are wildly different parts, though. :-?

http://markingcodes.com/search/c/200a
http://markingcodes.com/search/c/26a

See the snubber components in this example:

https://www.eeweb.com/wp-content/uploads/articles-articles-flyback-transformer-design-1387179412.png
« Last Edit: July 17, 2024, 05:42:05 pm by fzabkar »
 

Offline Peter TryndochTopic starter

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Re: What is this part and resistor value
« Reply #2 on: July 18, 2024, 09:01:26 am »
Somehow I don't think the value of that shunt resistor is 4R9
Does anyone want to have a go at reading the colour code?
Just blew another shunt, chip and transformer primary.
Transformer rerewinding time - fun!
Luckily I bought 10 chips. Foresight?

What is my luck in getting a schematic?
Device: Electrolux clothes dryer EDP2074PDW
Circuit board 0194_0003 G

BTW Thank you  fzabkar for explaining TRSB1
 

Online PA0PBZ

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Re: What is this part and resistor value
« Reply #3 on: July 18, 2024, 09:45:44 am »
Unfortunately the service manual does not have schematics but it does have a better picture of the resistor:



I'd say it's 47 Ohms.

(At least when that's the resistor you are referring too)
Keyboard error: Press F1 to continue.
 

Offline Peter TryndochTopic starter

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Re: What is this part and resistor value
« Reply #4 on: July 18, 2024, 10:11:18 am »
47R sounds better.
The board looks slightly different but the colours seem to match what I have found online.
I have attached some more pics of the resistor.
 

Online bastl_r

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Re: What is this part and resistor value
« Reply #5 on: July 19, 2024, 10:19:22 pm »
Hi
This is a fuseresistor.
Its vaule ist 4R7.
Black at the 3th ring is .0
 

Offline Peter TryndochTopic starter

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Re: What is this part and resistor value
« Reply #6 on: July 20, 2024, 12:02:28 am »
In my last attempt I used a regular 5R6 shunt resistor (not knowing that it needs to be fusible)
I blew the resistor, chip (new replacement) and transformer primary (which was 15R)
So I don't know what is left in the primary that could be at fault.
Could a failure in the low voltage section cause such a catastrophic failure?
The output windings on the transformer measure in the 0R2 range, but this would be typical I would think.
Measuring with the transformer removed, on the low voltage side I get readings in the Megohms or open, so no short there.
 

Online Wallace Gasiewicz

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Re: What is this part and resistor value
« Reply #7 on: July 20, 2024, 12:11:17 am »
F The last band is white. it is a fusible resistor.  Black in this position means wire wound
The other colors are (I Think I can see the Colors)_     
Yellow  =   4     
Purple  =   7   
Black    =  0    Multiplier   
Gold     =  Tolerance
So        47 Ohms Fusible   
The original resistor blew because of failure in the circuit. It did it's job.
 


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