Blew this capacitor plugging in wrong power plug on this analytical balance scale. Nothing else looks blown or burnt. Is this analytical balance scale salvageable once i replace the capacitor or is the pcb board most likely screwed?. I could not locate any fuse to protect the pcb board from over voltage.

 

Replace the capacitor and see what happens.

 

Blew this capacitor plugging in wrong power plug on this analytical balance scale. Nothing else looks blown or burnt. Is this analytical balance scale salvageable once i replace the capacitor or is the pcb board most likely screwed?. I could not locate any fuse to protect the pcb board from over voltage.

There's absolutely no way for anyone to look as a bunch of pictures and say whether or not anything else was damaged. The fact that the power supplied was sufficient to destroy that capacitor is not a good sign, so it is likely that something else was at least stressed and possible damaged, if not destroyed. The real question is how willing are you to take the chance that nothing else was damaged? You might replace the capacitor and everything might seem like it's working, but is it really working properly? Does it continue to operate within spec? Will it continue to operate within spec down the road as if nothing had happened? For your application, does it matter whether it operates within spec or not? If it does, are you confident that you can detect that it has gone out of spec before something bad happens?

 

There's absolutely no way for anyone to look as a bunch of pictures and say whether or not anything else was damaged. The fact that the power supplied was sufficient to destroy that capacitor is not a good sign, so it is likely that something else was at least stressed and possible damaged, if not destroyed. The real question is how willing are you to take the chance that nothing else was damaged? You might replace the capacitor and everything might seem like it's working, but is it really working properly? Does it continue to operate within spec? Will it continue to operate within spec down the road as if nothing had happened? For your application, does it matter whether it operates within spec or not? If it does, are you confident that you can detect that it has gone out of spec before something bad happens?

Hey yeah I just needed other knowledgeable peoples opinion on basic diagnosing this pcb board further from the capacitor. As for specs I have calibration weights to check periodically to see if its within spec.

 

Hey yeah I just needed other knowledgeable peoples opinion on basic diagnosing this pcb board further from the capacitor. As for specs I have calibration weights to check periodically to see if its within spec.

If you are willing to take the risk instead of just replacing the entire board -- and that depends on so many things that only you can gage -- then I'd recommend replacing the capacitor and seeing if the board will calibrate. Then exercise the board quite a bit over some period of time (you decide what 'a bit' and 'some period' mean) and check if it is still within calibration. If you are then reasonably comfortable, I'd recommend rechecking the calibration more frequently, say 1/4 the normal time interval, for the first few normal periods before you have faith moving forward.

 

My question was if the capacitor that blew if it was acting as the fuse protecting the board from over voltage. I cant locate a fuse on the board.

 

My question was if the capacitor that blew if it was acting as the fuse protecting the board from over voltage. I cant locate a fuse on the board.

There's no way to tell. It would depend on where in the circuit that cap was and whether it failed as an open or as a short and whether it failed before or after some other component was damaged. Way too many variables. If it did happen to protect the rest of the board, it's not because of any intentional aspect of the design.

 

My question was if the capacitor that blew if it was acting as the fuse protecting the board from over voltage. I cant locate a fuse on the board.

Electrolytic capacitors can usually hold higher voltages for a short time than the nominal ones.
They are less sensitive to an overvoltage than other components, so I guess, there's more damaged components on the PCB.
Either way, replace it and apply the voltage again and see if the device works

 

The wrong power supply may not just be the wrong voltge it may also be the wrong polarity or at may be AC output instead of DC.
Les.

 

Also check the yellow rectangular thing near the capacitor. It may be some form of fuse or resetable fuse. By the looks of the board, it should be conductive, feeding that cap. Hard to tell for sure. It might also just be another type of capacitor....
But like others say, hard to tell if anything else is blown. Odds are high that there will be other components destroyed as well.

 

it was the voltage regulator chip. I replaced the chip and capacitor and now the scale works.