Question about Generac 100 Amp 120/240-Volt Transfer Switch #RTSN100A3

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10kw Generac Guardian not cranking, shows rpm sense loss

After installation, followed installation guide's instructions for manual test. Utility power off. Breakers on Generac panel off. Generator's breaker off. Generator's mode switch set to off. Manually operated transfer switch to down position. Switched generator's mode switch to Manual start ... readout ''cranking, attempt 1'' for a few seconds ... but no cranking whatsoever, whole unit is silent ... then ''RPM Sense Loss'' message.

Verified natural gas pressure is present. Battery's brand new and shows full charge. 12 volts present at lug under red cap by starter. Fuse is good.

Posted by bobsykora on

  • bobsykora Sep 08, 2009

    The Mode switch has three settings: MANUAL, OFF, and AUTO. The step-by-step installation guide tells me to put it at OFF till utility power is disconnected and manual transfer has been thrown, then switch to MANUAL.

    BTW, when I put the Mode switch to AUTO and disconnect utility power, the readout tells me it's going through a utility disconnect delay, then says it's cranking (it isn't), then gives the same RPM SENSE LOSS error message that results when I go through the manual test.



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Sounds like Generator mode switch should be "ON".

Posted on Sep 08, 2009


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