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Electronics => Beginners => Topic started by: boatanchorguy on January 15, 2018, 04:40:53 pm

Title: Bridge Rectifier Dissipation
Post by: boatanchorguy on January 15, 2018, 04:40:53 pm
With a basic 4 diode bridge rectifier where there is no load - just open circuit on the output side - am I correct that the only energy expended in this system would be heat due to the voltage drops across the diodes? 
Title: Re: Bridge Rectifier Dissipation
Post by: rx8pilot on January 15, 2018, 04:44:15 pm
An open circuit has no current. Without current, there is no heat.

Short and misplld from my mobile......

Title: Re: Bridge Rectifier Dissipation
Post by: TimNJ on January 15, 2018, 05:18:29 pm
Not sure the context of your question but yes, without any current, there cannot be dissipation.

On a side note, if you try to probe a bridge rectifier open circuit (or effectively open circuit with a 10M scope probe), you may see some weird nonlinear waveforms. Apply a little load to it and you’ll see what you’d expect.
Title: Re: Bridge Rectifier Dissipation
Post by: madires on January 15, 2018, 05:37:50 pm
There would be a negligible small power loss because the diodes have a tiny leakage current.