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I am trying to understand What happens when the Electrolytic caps fail at the input terminal of a charger? What about at the output of the bridge rectifier? These two caps below are rated 100uF @ 200V. The input is 115 AC, 60Hz. These caps are currently bad, you could see that they already have vented. They're measuring low, ~ 32uF instead of ~ 100 uf and the ESR is higher than normal. That means it will heat up more than usual due to the higher ESR and it will allow for more voltage ripple. Is that enough to cause the charger not to work?

enter image description here

Then there is another film cap (Polypropylene) at the output of the bridge rectifier. The Fluke refused to read it, it kept saying OL. It's estimated to be 39nF (I compared it to a similar film cap of it's size) It apparently also failed. I am trying to understand if this cap failed how would it affect the rest of the circuit?

Those are the only damage to the board, mostly cap failures. Do you think If I replace them the charger will go back to normal? I would appreciate good feedback. Thank you

enter image description here

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What happens when a Cap fails?

The device will fail to function properly

They're measuring low, ~ 32uF instead of ~ 100 uf and the ESR is higher than normal. ...Is that enough to cause the charger not to work?

No.

Those are the only damage to the board, mostly cap failures.

Those are only damages that are VISIBLE. There could be totally fried ICs, diodes, transformer coils shorted, etc, which might be non-visible.

Do you think If I replace them the charger will go back to normal?

You can try, but going back to normal functionality has a very remote chance.

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  • \$\begingroup\$ Thank you. Broadly speaking then, electrolytic caps at the input and output of a power supply will not cause the supply to stop functioning it will just not perform as it should. \$\endgroup\$ – Rocky79 Apr 6 at 1:18

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