Wireman · Generators & backup troubleshooting · 2023 NEC ·
Generators & backup
Generators, transfer switches, UPS.
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Generator runs but no powerBreakers, GFCI, then output voltage and frequency at the generator.Up to 2 stepsTransfer switch won’t transferIs the generator source acceptable to the switch, are timers running, and is the switch able to move?Up to 4 stepsGenerator trips under loadOverload, a big motor start, an unbalanced leg, or a ground fault on the generator.Up to 2 stepsPortable generator and inlet: no powerGenerator, cord, inlet and interlock, one link at a time. Never a dryer outlet.Up to 4 stepsStandby generator fails its exerciseBattery, charger power, controller settings and fuel. Engine work goes to the dealer.Up to 3 stepsUPS alarming or stuck on batteryInput power, overload, then the batteries.Up to 2 steps