Speaker Relay and DC Detect/Protect.

[xXBrunoXx]

Hi, Would a Normally Open Relay be better then normally closed for Speaker connection, avoiding " contact sticking" ?. Tho , the more I think it would make no difference than using normally closed or than using just one Relay.

 

[Jeffh01]

If not going down the SSR route, I’d use one n/o relay and ground the n/c contact to quench any arc that would otherwise pass through the speaker. You can probably use a transistor instead of the first relay here.

 

[Mark Tillotson]

The arcing will all be over by the time the common connects to the NC terminal... Freewheel diodes are a better strategy for dissipating energy from a driver coil.

 

[xXBrunoXx]

Can you please draw quickly , paint will do. As Im not sure what you mean by the common on Normally closed terminal.

 

[Jeffh01]

As in 0V or common ground. Mark is right about the freewheeling diodes.