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mrunella's avatar
mrunella
Explorer
Aug 24, 2021

30amp Gen/50 Amp RV Generator Help

Alright folks, need your help as I am at a lost on this one. We have a 2022 Thor ACE 32.3 Motorhome that uses “50 amp” service. I have a Firman Generator that has the TT-30R receptable on the side (30amp/3650 watts/120). We would like to be able to run our RV off this generator (obviously I know I won’t be able to run both AC’s and the microwave at the same time). Coach keeps coming across with “SHORE POWER DEFAULT” code. I know that a lot of people are able to run their 50amp RV’s off 30amp service, just have to be very careful to not overload it (i.e., AC units, microwave, etc.). Thoughts?

I have tried…
Generator (30amp) with 30amp to 50amp dog bone connector to 50 amp cord to COACH: NO GO
Generator with 30 amp cord directly to coach meeting a 30 AMP to 50 amp connector into the coach: NO GO

This worked perfect on our other coach, any thoughts?
  • JCK's avatar
    JCK
    Explorer
    Aug 24, 2021
    Maybe your running through a surge protector that’s detecting a open ground . Other people have said if that’s the case you need a neutral grounding plug and plug it into one of your 110 outlets . Some one will come along and discripe this better
  • rlw999's avatar
    rlw999
    Explorer
    Aug 24, 2021
    RV generators have the neutral and ground bounded (as do shore power connections), so your EMS is probably faulting when it doesn't detect that bonding.

    Your generator may have a way to connect a bond strap, or you can buy (or build) an RV bonding plug to plug into one of your generator's 120V 20A plugs:

    Southwire CompanyNeutr al-Ground Bonding Plug

    Most 30A->50A adapters will connect both 50A hots together (so you get power on both hots), so it's possible that your EMS is complaining about that, but it's most likely the neutral-ground bond.
  • bob213's avatar
    bob213
    Explorer
    Aug 24, 2021
    Make a neutral bonding plug yourself for a couple of dollars.
    Watch here starting at 1:45 plug


  • time2roll's avatar
    time2roll
    Nomad
    Aug 24, 2021
    mrunella wrote:
    Coach keeps coming across with “SHORE POWER DEFAULT” code.
    Need to disable this item giving the error. Or a bonding plug is needed.
  • way2roll's avatar
    way2roll
    Navigator II
    Aug 24, 2021
    Why are you running a stand-alone generator for an RV that came with it's own built in? Is this a joke?
  • bobsallyh's avatar
    bobsallyh
    Explorer II
    Aug 24, 2021
    According to Thor specs Onan® RV QG 4000 Gas Generator is an option on this model.
  • road-runner's avatar
    road-runner
    Explorer III
    Aug 24, 2021
    way2roll wrote:
    Why are you running a stand-alone generator for an RV that came with it's own built in? Is this a joke?
    I can't speak for the OP but can say I do exactly this because the built-in onan is so darn noisy.
  • Baja_Man's avatar
    Baja_Man
    Explorer
    Aug 31, 2021
    When combing two inverter/generators via the parallel kit, is a neutral-ground bonding plug needed for each inverter?
  • DrewE's avatar
    DrewE
    Explorer II
    Sep 01, 2021
    For the usual paralleling systems/setups, only one is needed. The parallel kit simply wires the higher-capacity output receptacle to both generators: the hots all tied together, the neutrals all tied together, and the grounds all tied together. The actual "magic" that makes paralleling work is built into the generators themselves. Anyhow, since the neutrals and grounds are tied together across both generators, putting the bonding plug in one generator bonds the whole system.

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