Can you run a onboard generator with an external generator!

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Sep 26, 2020
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I have a 50 amp Lithium 2414 TH with2 AC units. I have a onboard Onan 4000 generator installed. I can only run one AC at a time with the 4000 watt onboard generator. Can I or how do I hook up an external generator so I can run everything with a internal and external generator. I was told I can run a 4000 watt inverter generator externally along with the onboard Onan. Please advise and thank you in advance.
 
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I think this can be tricky. I am assuming that you want to feed additional 120VAC to the on-board inverter rather than 12VDC to the low-voltage electrical system. Phasing of 120VAC comes into play and, if you get it wrong, substantial damage can be done.

If you are talking about feeding 12VDC directly to the low-voltage electrical system, I'm not sure how you can do it. It may be possible but is outside my area of expertise.

In either situation, I would strongly suggest consulting a qualified electrician.

TJ
 
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I would say no you can't. Inverter generators that will tie together tie the DC bus together and use one inverter. Most inverters will fail if left in the circuit when other source is applied. This includes UPS systems as they have sensing circuit and relays to be certain only one system is engaged at one time. Two generators could be tied together if they are both standard generators by using a meter to time the connection and then they would work as a servo type system.

Two methods do work. Wire one AC to it's own external cord, or
Use a large enough inverter to power everything and supply large cables connected to the battery bank from the generator. Because I use a large inverter and seldom connect to the grid, I use this method. My external generator that supplements my battery bank is what is called a poor boy generator that is an automotive generator connected to a gas motor. Between the poor boy and solar I can run most anything I have.
 

Jim

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My input, for whatever it's worth.

I have a 50 amp Lithium 2414 TH with2 AC units. I have a onboard Onan 4000 generator installed. I can only run one AC at a time with the 4000 watt onboard generator.
I would have thought your generator would handle both of these at the same time. But I guess you wouldn't be here asking questions if that were the case, right? Let me ask, did you add the second air conditioner yourself?

Also, there is a good possibility that putting a "soft start" device on the air conditioners will avoid the "surge" necessary to fire them both up. I've seen this work for lots of people who want to run two air conditioners but the "surge" is more than the generator can provide. Here is a link to some that you can research.

Can I or how do I hook up an external generator so I can run everything with a internal and external generator.
I can't image that being possible. It's not like adding a second water source to an existing water source, and getting twice the volume, which is what It sounds like your thinking. But as @Kevin D Pem mentioned, you could separate one of the air conditioners from the main wiring and then wire it independently to the external generator, and run it that way.
 
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Joined
Sep 26, 2020
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Thanks all for the good information. Not the answer I was looking for, but what I thought would be correct. I didn't think running both was an option, but had to ask. Anyway, ill look into the soft start and just run one at a time for now. Thanks again and happy Camping!!
 
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