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Old 21st Nov 2022, 10:56 pm   #5
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Default Re: Should I Replace Just Two Blown Diodes in a Bridge Rectifier or all Four

Quote:
Originally Posted by stevehertz View Post
FWIW - wrong as it seems! - I'd only replace the ones that are faulty.
No....false economy! I used to think the same BUT a couple of times I did just that and either one or the other diodes would fail soon after. 40 years experience in the trade has proved that changing all four is the most reliable way and avoiding call-backs. As has been pointed out, diodes are cheap....only pence usually so not worth scrimping. Consider also that when a diode (or two) in a bridge go short, there is a tremendous current passed through the smoothing cap as the poor thing passes AC for one half-cycle. Before any fuse blows the two remaining diodes pass a current well beyond their design, tens of amps probably. That is not going to do them any good at all. Replace all four with the same type or better.
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