Atlas Copco QAS 108JD Manuel D'instructions page 61

Engine Circuit Wiring Diagram
1310 3011 38
N12 - Synchro Start
wires from Mag P/U come here. 4-5 volts. if the
engine over speeds then the voltage will be higher
and the engine will shut down. #5 wire from controller
feeds this. The Barber Coleman/ Woodward governor
senses engine speed and will keep 60 HZ
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