Question for any electrical gurus: All modern light planes have a starter contactor and/or solenoid to handle the starter current. They also have a switch to turn off the regulator/alternator, which could be putting out a large number of amps.
So the question is:
If the purpose of the main relay is to avoid switching high current with the master switch, but you turn off all your lights/pumps/avionics/etc before you turn off the master switch, then why would you need a main relay? Likewise, if you don't turn on your lights/pumps/avionics until after you turn on the master switch and get the engine running, then the main relay is pointless, no?
So the question is:
If the purpose of the main relay is to avoid switching high current with the master switch, but you turn off all your lights/pumps/avionics/etc before you turn off the master switch, then why would you need a main relay? Likewise, if you don't turn on your lights/pumps/avionics until after you turn on the master switch and get the engine running, then the main relay is pointless, no?
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