this post was submitted on 02 Jul 2025
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I have a controller for an electric throw blanket that I would like to repair, but I have no experience soldering on boards

You can see at bottom left a yellow box and a resistor. Something has burnt out in this area, and likely both will need to be replaced at a minimum

I would also need help identifying parts. The yellow box is embossed 'Tenta' and has printed on the side 'TC MEX/TENTAMKP 0.1 uf 275VAC' with some other markings obscured or damaged

Is this an achievable project?

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[–] [email protected] 16 points 1 week ago* (last edited 1 week ago) (4 children)

Honestly this is not worth the risk, It looks like a simple enough repair a high watt resister a cap and possibly an IC (U1 looks burnt) BUT consider this, something happened to cause the failure and that something could still be around, like a short in the heating element of the throw. Whoever designed this obviously did not test the failure mode of the device. The reason things are UL rated (other certs for non US) is that they get tested and found to not fail in a manor that will cause harm to the user or fire. The failure mode of this device could cause a fire, if you repair it and the same thing happens. . . . Don’t risk it, Toss it out.

ALSO NOTE! if you do attempt it. That cap is most likely a class X2 cap and would need to be replaced with the same, don’t use just any cap!

[–] [email protected] 4 points 1 week ago (2 children)
[–] [email protected] 9 points 1 week ago (1 children)

It’s a “safety capacitor” used across AC, similar to a Y cap, they have a known failure mode that is designed to not cause fire.

https://www.allaboutcircuits.com/technical-articles/safety-capacitor-class-x-and-class-y-capacitors/

[–] [email protected] 2 points 1 week ago

Oh! Very cool! Thank you very much!

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