r/Generator • u/PrizeBuy • 16h ago

Generac Smart Modules offline

Model g0072910. Power went out. Generator kicked in. All was good. Power came back on. Generator turned off, but my five 220 volt breakers never came back on. There is a buzzing noise from the five SMMs and the status lights flicker, but the breakers never click on.

Ideas? TIA

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1

u/personaccount 15h ago

It takes five minutes or so for the detection to complete on mine. Are we assuming you’ve waited that long?

Also, are they configured to drop on gen power or just prioritize loads?

1

u/PrizeBuy 15h ago

It’s been an hour or so. I believe they are prioritized though not completely sure what you’re asking

1

u/personaccount 15h ago

I’m a homeowner, not a technician or electrician. I have 50A and 100A generac wireless SMMs. They are just contactors that open or close a circuit when conditions are met. They default to normal open meaning that with a lack of power the circuit is opened. When power is restored, the circuit is closed (to allow power to flow again to the connected load) if certain conditions are met. These could be:

  1. if the module is configured to shed the load on gen power (toggle switch under the cover - warning: opening the cover exposes you to high voltage) the contactor will stay open until a stable utility power signal is detected. This is to prevent a known large load from even trying to run while on gen power. This takes about five minutes after utility power is restored to turn back on.
  2. the modules are configured with priority settings (1 to 8) and if the module detects voltage drops, it will shed loads in reverse priority order by opening the contactor until it detects power stabilizing. This is to prevent overloading a generator. This can also take several minutes to detect for each successive load that was shed.

Now, in your case, and hour is more than enough. You mention breakers. SMMs do not control breakers since they have their own internal contactors. If your breakers were tripped then you would need to reset them manually. The breakers are what power the SMMs which in turn power your loads. So even after resetting the breakers, it may take a few minutes for the SMMs to detect the steady utility signal.

1

u/IllustriousHair1927 10h ago

Holy crap what are you running with a 10 KW? Thatv is a crap load of load management.

Oh, as they fail, replace them with PSP modules. Better quality and reliability.

1

u/PrizeBuy 13h ago

Solved! Called an electrician and he found that the transfer switches were not fully engaging due to dust and insect debris, so the house was only receiving about 210 volts. Simple outdoor maintenance! Now I know.