Most Common Mode of OT Failure

peteb

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I think biggest possibility for a Flyback-phenomenon failure is when playing loud and single loudspeaker or series connected loudspeakers voice coil circuit fails or speaker cabinet cable detach.

thanks 2L Man.

that makes sense that the worst case is while signal is being processed for the speaker load to go open, in that order.


I wonder why the wikipedia article I linked states that fly back diodes are for the case where power supply, not the load, suddenly cuts out.
 

2L man

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thanks 2L Man.

that makes sense that the worst case is while signal is being processed for the speaker load to go open, in that order.


I wonder why the wikipedia article I linked states that fly back diodes are for the case where power supply, not the load, suddenly cuts out.
That explain normal operation, not faulty operation. Relays either get current and contacts close and then coil current is cut and contacts open and same time the current thru coil turns to high voltage spike. When relay drive is done using a transistor or a micro chip the diode is essential or they destroy. It is good practice to install a diode even a switch is used to control the relay or contactor because without diode the voltage peak wears switch contact.

For switches turning DC off is wearing operation and without a diode over the relay coil it comes much more wearing.
 
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