Question about Generac Guardian 100 Amp Transfer Switch NEMA 3R

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Suddenly in power outage and engine starts auto., NO inside power

9-3-09 -- A very recent problem with a 3 year old new house installation of 16kW Generac with 100A exterior transfer switch feeding seperate inside distribution box is, when power goes off, while the generator NG engine starts up automatically, no power in house. The transfer switch does NOT trip automatically as previously. When I trip manually with yellow lever, while engine continues to run, still NO electricity. Thruout this time, the green LED remains flashing "utility not sensed" AND the 65A circuit breaker on control panel in unit remains ON. All breakers have been switched on and off just to be sure OK. When main power is restored, generator shuts itself down in <60 secs. Problem continues when power outage is simulated by tripping main breaker. All oil, filter and plug changes faithfully made on yearly basis. Does it sound like transfer switch or controls or ? Your comments, please? ****

Posted by Anonymous on

  • Anonymous Sep 05, 2009

    Good question. While there is NO power to distribution panel inside the house when engine is running, even when I manually operated transfer switch. I don't know how to determine IF the generator itself is operating? There are no red LED's flashing when engine is running except the green flashing LED that apparently just means utility is not sensed. The is no convenience outlet built into unit itself. Do you have any ideas on how to determine if generator is functioning, please?



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Posted on Sep 04, 2009

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  • Anonymous Sep 06, 2009

    u hav 2 hav a/c volt reading @ board via gen. make sure of gen wire input location

    if u put load 2 these wires ie 100 watt extension lead light it shood work

    u r dealing with lethal power

    i hope house and gen r R.C.D


    good luck roosterone



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