I have a 2007 Nimbus36. It has a command 30 running a Onan 8000 gen. set. When the command set is set to auto, it will start the gen set when the batteries are low, but it will not shut off when they are charged. I took it to a RV shop in Or. and they put a new command 30 module in it. They had it for two weeks and could not figure it out. Yes I had a nice bill. I have new coach batteries and a Freedom sw 3012 converter/inverter put in at foretravel tx. last fall. I have had the coach for two years and the generator has never turned itself off. Any ideas. Thanks Louis.
Moderator Jeff edited title for clarity.
This may help...
Auto genset starts but doesn't automatically shut down - Winnebago Owners... (https://www.winnieowners.com/forums/f260/auto-genset-starts-but-doesnt-automatically-shut-down-361731.html)
Your genset starts on low voltage, so it should stop on high voltage. Id Est, the Cummins EC-30 board is "seeing" the battery voltage. Maybe the stop at voltage has been set too high? Perhaps lowering the voltage to 13.6V would give you at least a "proof" that the board is functioning correctly? Conversely maybe setting the Start at voltage to something less than 12.0V might give you something to consider?
From page 9 of the Cummins Onan Operator and Installation Manual.
STOP @ V
The STOP @ V is the voltage to which the house
battery must rise to cause the genset to automatically stop due to a full battery. The default value is Auto
which stops the genset when three bars are displayed
in the battery level indicator. See the Operation section
of this manual. The STOP @ V voltage range is 13.2-
14.5 volts. A lower voltage will not fill the battery as full
but it will reduce the amount of time the genset will run.
A higher voltage will fill the battery to a higher state of
charge, but increase the amount of genset run time. If
the charge system is unable to reach the STOP @ V
voltage, the result will be excessive genset running.
This setting does not change the battery charging voltage. Do not set STOP @ V above the voltage of
the battery charger.
https://www.cummins.com/sites/default/files/2018-08/900-0541B-energy-command-operation.pdf