CTEK MXS 7.0 Battery Charger - What Is The Burnt Out Resistor?

[mackembazza]

I have a CTEK MXS 7.0 which died. Resistor R1 has burnt out so I can't see all of the coloured rings and was wondering if someone on here new the value. The first ring is yellow, second is totally burnt, 3rd might possibly be black (but can't be sure) then 4th and 5th are gold. If 3rd ring is definitely black then I know it's likely to be 40, 43 or 47 Ohms. Hoping someone can confirm please?

[yanalesch]

Does your circuit look like in the picture I found online? And is it the same resistor that burnt?



If yes, reffering to this german forum: https://www.7-forum.com/forum/archive/index.html?t-167268.html

It is an 33 Ohms resistor with ~ 1 Watt . The early revisions had an 24 Ohms resistor, and later revisions got an 33 Ohms resistor. But it is unlikely that the resistor is the culprit, you may consider to track which components are in series to it. In the forum I refered to the mosfet also was defective.

[mackembazza]

Does your circuit look like in the picture I found online? And is it the same resistor that burnt?

(Attachment Link)

If yes, reffering to this german forum: https://www.7-forum.com/forum/archive/index.html?t-167268.html

It is an 33 Ohms resistor with ~ 1 Watt . The early revisions had an 24 Ohms resistor, and later revisions got an 33 Ohms resistor. But it is unlikely that the resistor is the culprit, you may consider to track which components are in series to it. In the forum I refered to the mosfet also was defective.

Unfortunately that one is different. Mine is a bigger resistor, probably 2 or 3watts, and is hidden under a heatsink. Thanks for your suggestion.

[yanalesch]

Maybe the images in this threads can help you:

http://www.ittsb.eu/forum/index.php?topic=937.0

https://www.mikrocontroller.net/topic/351174