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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default Does this sound right? - NEMA question

"Roger Long" wrote in
:

3) A NC relay wired into the starter circuit that disconnects the
instruments when the starter button is pushed. When the button is
released however, isn't there a chance that the magnetic fields could
still be collapsing through the starter coils after the relay
releases? I was taught on aircraft that shutdowns are more of a hazard
than starts. Same GPS restart issue as above.


Relays aren't that fast. That would work fine. You could also INCREASE
the dropout time of the relay with a big electrolytic capacitor across the
relay coil that would hold it closed until the capacitor discharged through
it....just a few hundred milliseconds would be necessary....

Of course, with the momentary shutdown, you'd have to reboot all the stuff
because it all uses electronic power switching, not an on-off mechanical
switch...which takes some time.

Larry
--
We'll watch for your boat....(c;