Forum Discussion

rdmike's avatar
rdmike
Explorer
Jun 11, 2017

Auto Gen Onan EC30

I have a class A DP with a Onan Generator. The control panel has a EC30 auto gen set.

We have a small dog, and we would like to program the EC30 to start up on the HVAC demand. This works fine.

The problem I have or want fix is that it does not detect AC shore power. Basically the EC30 works and starts the gen set when dry camping when it signals the HVAC demand or coach batteries are low.

Further reading in the manual states thar an optional sensor can be installed to the EC30 that detects AC shore power that will not allow the genset to start, but will start if the demand is given by the HVAC or low batteries and no AC shore power detected.

My ultimate goal is if the AC shore power was to be interupted at a RV park, the EC 30 detects this, and if the HVAC demand triggers, the gen set automatically turns on, and when AC shore power resumes the gen set turns off.

The manual says the sensor is a 120VAC transformer to 12Vdc wired to lines 13 and 14 of the EC30.

Does anyone have this on their coach? Is it just a simple transformer?

Thanks is advance.
Class A
  • larry_cad's avatar
    larry_cad
    Explorer II
    Jun 11, 2017
    Here is an excerpt from the owner manual:

    "Testing Shore AC Present

    This test verifies that the EC-30 can sense when AC
    power is available from the utility grid. Before starting
    this test be sure that the Shore AC is disconnected.
    Turn off the AC breaker at its supply or unplug the
    vehicle or trailer from the AC grid system. Do not do
    this test with the genset running. Navigate to the
    Shore AC Present display and press ENTER. The
    display will say Turn On Shore AC. Now plug the
    shore AC back in or turn the breaker on. The display
    will change to read AC Ok ENTER. Press ENTER to
    exit the test."

    You can do this to determine if you have the option installed
  • Belgique's avatar
    Belgique
    Explorer
    Jun 11, 2017
    RDMike, just had a long discussion on this in one of the other RV forums for the same reasons you want it. Turns out that Fleetwood didn't connect what was needed in that era. Mine is a 2007 40X.

    A chap did a lot of research on it and figured out how to wire it but it involves running a wire from the back of the rig to the EC30 panel and some other stuff that's beyond me. If you care, I'll see if I can find a link to it but it won't be for a few days because we're going to a CG where web is tough to access.
  • rdmike's avatar
    rdmike
    Explorer
    Jun 11, 2017
    larry cad wrote:
    Here is an excerpt from the owner manual:

    "Testing Shore AC Present

    This test verifies that the EC-30 can sense when AC
    power is available from the utility grid. Before starting
    this test be sure that the Shore AC is disconnected.
    Turn off the AC breaker at its supply or unplug the
    vehicle or trailer from the AC grid system. Do not do
    this test with the genset running. Navigate to the
    Shore AC Present display and press ENTER. The
    display will say Turn On Shore AC. Now plug the
    shore AC back in or turn the breaker on. The display
    will change to read AC Ok ENTER. Press ENTER to
    exit the test."

    You can do this to determine if you have the option installed


    Thanks Larry, I had already done this and no option installed.
  • rdmike's avatar
    rdmike
    Explorer
    Jun 11, 2017
    Belgique wrote:
    RDMike, just had a long discussion on this in one of the other RV forums for the same reasons you want it. Turns out that Fleetwood didn't connect what was needed in that era. Mine is a 2007 40X.

    A chap did a lot of research on it and figured out how to wire it but it involves running a wire from the back of the rig to the EC30 panel and some other stuff that's beyond me. If you care, I'll see if I can find a link to it but it won't be for a few days because we're going to a CG where web is tough to access.


    Thanks Belgique, I was wondering, why a simple transformer, 120Vac to 12vdc connected at the nearest AC source would not do the trick? (Providing the AC source is not connected to any inverter source.) Once there is no power to the AC source, the EC 30 would sense this through no 12VDC input and start the Gen set on a HVAC demand?

    I am just wondering why the wiring would need to be run from the back of the rig?

    My next step will be to open up the EC30 and see if there are any wires attached to terminals 13 & 14. As the coach might be wired for it, yet no sensor.
  • phays's avatar
    phays
    Explorer
    Jun 11, 2017
    The EC30W remote unit I have comes ready to do what you want to do. The instructions say plug the power transformer into a circuit that is not on the inverter. When the transformer loses power with the loss of shore power, the EC30W then senses the loss of power and if needed will start the genset. I would assume a typical 12 volt brick power supply would do the job for you.

    I plug my EC30W into a receptacle that is powered by the inverter but when I'm in a campground I turn off the inverter.
  • tderonne's avatar
    tderonne
    Explorer
    Jun 12, 2017
    rdmike wrote:

    Thanks Belgique, I was wondering, why a simple transformer, 120Vac to 12vdc connected at the nearest AC source would not do the trick? (Providing the AC source is not connected to any inverter source.) Once there is no power to the AC source, the EC 30 would sense this through no 12VDC input and start the Gen set on a HVAC demand?

    I am just wondering why the wiring would need to be run from the back of the rig?



    The 120 volt source also can't be connected to a source that the running generator would supply in some versions of the EC30. This may be the reason the wiring needs to go all the way to the back, to get to a shore power source.
  • rdmike's avatar
    rdmike
    Explorer
    Jun 12, 2017
    phays wrote:
    The EC30W remote unit I have comes ready to do what you want to do. The instructions say plug the power transformer into a circuit that is not on the inverter. When the transformer loses power with the loss of shore power, the EC30W then senses the loss of power and if needed will start the genset. I would assume a typical 12 volt brick power supply would do the job for you.

    I plug my EC30W into a receptacle that is powered by the inverter but when I'm in a campground I turn off the inverter.


    Thanks but I dont have the wireless unit. Very different.
  • rdmike's avatar
    rdmike
    Explorer
    Jun 12, 2017
    tderonne wrote:
    rdmike wrote:

    Thanks Belgique, I was wondering, why a simple transformer, 120Vac to 12vdc connected at the nearest AC source would not do the trick? (Providing the AC source is not connected to any inverter source.) Once there is no power to the AC source, the EC 30 would sense this through no 12VDC input and start the Gen set on a HVAC demand?

    I am just wondering why the wiring would need to be run from the back of the rig?



    The 120 volt source also can't be connected to a source that the running generator would supply in some versions of the EC30. This may be the reason the wiring needs to go all the way to the back, to get to a shore power source.


    You make a good point. Wasn't thinking it through. The genset would give me power to my AC outlet thus turn off /on (cycle) the genset. Back to the drawing board!

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