cancel
Showing results for 
Search instead for 
Did you mean: 

30amp Gen/50 Amp RV Generator Help

mrunella
Explorer
Explorer
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?
13 REPLIES 13

way2roll
Navigator
Navigator
I don't think I have ever seen a MH in recent years that did not have a generator despite manufacturers calling them "options". Likely the dual air was the option with a QC5500 over the one air with the 4000. In either case I would bet dollars to donuts that it came with a genny. Maybe he had a problem with it, we'll never know.

Jeff - 2023 FR Sunseeker 2400B MBS

rlw999
Explorer
Explorer
way2roll wrote:
This appears to be a newbie hit and run post. I was really curious why the OP wanted to do this with an onboard genny. Guess we'll never know.


3 reasons I can think of:

1. Quiet - not only is is a small inverter generator quieter than the onboard generator, you can move it farther away from your unit.

2. Fuel efficiency, at low loads, his Firman 3650W will use about half the fuel per hour of an onboard QC4000. I used to wish that RV makers would include high quality inverter generators for better fuel economy and quietness, but now they are moving to Solar with Lithium batteries which can actually power the A/C for a while, which is even better.

3. CO safety - you have less chance of exhaust blowback when your generator is 20 or 30 feet from your RV.

But the most likely reason in this case - generators are often an extra-cost option, on the A.C.E. it's bundled with the dual A/C option so it's even more expensive than just a generator (and generators may be in short supply along with everything else, so maybe it would affect his delivery date).

I don't know what Thor charges for it, but list price on Onan 4000 is around $3500... list price on his Firman is $750. Of course, the onboard is much more convenient since you don't have to fuel it or walk outside to turn it on (though you can get portables with remote start).

On an older RV, it's also possible that the onboard generator stopped working and fixing it would cost more than the price of a portable generator.

way2roll
Navigator
Navigator
This appears to be a newbie hit and run post. I was really curious why the OP wanted to do this with an onboard genny. Guess we'll never know.

Jeff - 2023 FR Sunseeker 2400B MBS

DrewE
Explorer II
Explorer II
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.

Baja_Man
Explorer
Explorer
When combing two inverter/generators via the parallel kit, is a neutral-ground bonding plug needed for each inverter?
2023 GMC, 3500HD, Crew Cab, 6.6L Gas/6 Speed Auto, 4X4, Standard Bed; SRW
2011 Outback 250RS - Anniversary Edition
Equal-i-zer 10K

road-runner
Explorer III
Explorer III
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.
2009 Fleetwood Icon

bobsallyh
Explorer II
Explorer II
According to Thor specs Onan® RV QG 4000 Gas Generator is an option on this model.

way2roll
Navigator
Navigator
Why are you running a stand-alone generator for an RV that came with it's own built in? Is this a joke?

Jeff - 2023 FR Sunseeker 2400B MBS

wildtoad
Explorer II
Explorer II
Your unit didn’t come with its own Gen?
Tom Wilds
Blythewood, SC
2016 Newmar Baystar Sport 3004
2015 Jeep Wrangler 2dr HT

time2roll
Nomad
Nomad
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.

bob213
Explorer
Explorer
Make a neutral bonding plug yourself for a couple of dollars.
Watch here starting at 1:45 plug


You can avoid reality, but you cannot avoid the consequences of avoiding reality – Ayn Rand

rlw999
Explorer
Explorer
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.

JCK
Explorer
Explorer
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
2019 GMC Denali 2500 Duramax
2018 Grand Design Imagine 2500 RL