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Dr J Dr J is online now
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Join Date: Apr 2008
Location: Miami
Posts: 964
Quote:
Originally Posted by wilsonlaidlaw View Post
I am not sure you are correct there. If you look at the wiring diagram, the diode is connected across the primary coil of the relay not the contact side. I think therefore as others have said, it is there in order to short out the collapsing reverse surge current from the collapsing magnetic field of the primary. I have a high current diode from the car side of the battery master switch to earth, in case a rally marshal switches it off after an accident, without switching off the ignition first, to isolate the alternator and so that the master switch will also stop the engine. Again any reverse voltage from the alternator could in theory, damage various solid state devices like the DEM, noise reduction intercom and the digital rally navigation equipment.

Wilson
Ahhh yes. I see it in the diagram now. Interesting since most applications have it on the load side. In that case it seems you don't need the diode for SS relay.
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1979 SC, Slant nose wide-body cab conversion. AEM Infinity EFI, COP, supercharged!

Last edited by Dr J; 10-27-2018 at 05:56 PM..
Old 10-27-2018, 05:53 PM
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