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Can’t find a 0.35 ohm 5% resistor anywhere

bertus

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Nov 8, 2019
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Hello,

0.35 Ohms is not a standard value.
0.348 will be the closest, but with 5% tollerance, a wider change may apply:
vishay_color_E_series_big.png
Bertus
 

bertus

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Hello,

Why do you think the resistor is faulty?
It looks quite ok to me.
Did you measure the resistor?

Bertus
 

bertus

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Hello,

According to the table I posted, it could be a 0.36 ohms resistor.
That should be more easy to find.

Bertus
 

ZedsDeadd

Jun 27, 2021
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bertus

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Hello,

A 2 Watt resistor would be about 9 X 3.5 mm.

Bertus
 

73's de Edd

Aug 21, 2015
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You might also want to have a look (at) WHY the resi s tor burned.

Refer to post 7's photo of HIS board and then . . . . .
Look at the nearby . . . fractured outward . . . . case of a POWER FET and expect this burnt open part to be its source resistor, with the POWER FET being dead shorted internally.
 

bertus

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Hello,

@73's de Edd , Yes, you are right, the transistor shows severe damage.
@ZedsDeadd , Can you take a picture from the front of the transistor?
It will need to be replaced.

Bertus
 

ZedsDeadd

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1- screenshot of the same resistor that I found on google images

2- my blown resistor

3- transistor
 

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73's de Edd

Aug 21, 2015
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Sir ZedsDeadd . . . . .


All right now . . . . with R802's value being nailed down EXACTLY.

And since you could / did not come back with . . . the . . .or any . . .part numbering on the fractured power FET . . .don't you now think that it is due time that you should reveal this circuit boards numbering identifier, as well as its brand of manufacture and the sets model number.

The most to be seen from the snippet view of this board, is that it relates to a power supply board, with its related / assigned 800 series of device numbers.
The subject R802 resistor should be in the POWER FET source to ground and be having a current sense sampling voltage being fed back to the PWM controller.
BUT the instant that the junction on the POWER FET failed, it DUMPED the whole ~340VDC at 100'ish milliamperes (that's being ~34W . . .babycakes ! ) from the raw DC supply, right into this puny little 2W resistor.
So, you can now see the resultant double ended sparking /blasting out of that resistor, and expect that the now fused together FET D-G-S junction blob has ALSO sent a HEALTHY / 340V destructive voltage back down the gate feed path into the FET's controller IC.

This boards use of a Cy prefix for HV ceramic caps, relates to a similar assignment used by Samsungs.

Is this being your first attempt of repairing a board . . . instead of just your mass pulling of donor boards . . . . . ?

https://shortcircuitsolution.com/pages/about-us

https://www.google.com/maps/place/S...3b87c!8m2!3d35.0608551!4d-90.0004258?hl=en-US



73's de Edd . . . . . .

upload_2021-6-28_13-52-35.png






 

VenomBallistics

Aug 30, 2018
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Mother of Zeus child ... you might want to wipe the isotopes off that capacitor before you replace things too.
Looks like a scene of Saving Private Ryan was filmed in there.
 
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