Inverter on Generator wiring?

[timelinex]

I have a 2021 Grand Design 381m. I just put in 2 Lifepo4 batteries and am installing a Pure Sine Wave Inverter tomorrow. I am looking for the easiest way to do it before my trip next week.

I have a 5500 Onan generator, which is wired to a junction box in my battery compartment. From that junction box, the generator wires are wire-nut'd to wires that go to my transfer switch.

I know the "best" way of doing this is separating my panel into 2, adding another transfer switch so only one of them is energized, and running separate wires from the inverter to this setup..... But considering how often I will use the inverter and preferring an easy/fast install so I can have it for next weeks long trip...I've got a different idea.

Is there any reason I shouldn't put the inverter in the battery compartment, connect one end to my batteries, and add the inverter 120v wires into the wire nuts in that generator junction box?

I won't ever be running the generator at the same time. I also recognize that I have to flip my converter breaker off when using the inverter and be mindful of my use since the inverter is powering everything (a.k.a no AC...) I'm happy with all that. I'm just making sure there are no safety issues.

Thanks!

[timelinex]

Cptnvideo wrote:
You're welcome to come look at my setup. We'll be in Surprise until the end of October.
See signature in first post for equipment.

I appreciate the offer, but between 2 little kids, work and getting ready for our next trip....Time is scarce!

[Cptnvideo]

You're welcome to come look at my setup. We'll be in Surprise until the end of October.
See signature in first post for equipment.

[timelinex]

Alright everyone, I finished all the work today. I replaced my non-lithium converter with a new 60a lithium compatible one that I put by the batteries. I installed a Bluetooth shunt to monitor use. Then I installed the inverter by the batteries and put it on the wall.

I decided against tapping into the generator wiring with a manual switch. After opening the junction box, I decided to hook everything back up and skip this idea. Many reasons. I saw its some very heavy gauge wires leading out, which are a pain to work with. I would also need to custom fab a way to attach the switch to the box....or take out the box completely whoch would leave some ugly marks that I would have to fix as well. Lastly, while the switch is good, getting all that heavy gauge wire in there would be a major PIA.

I concluded that for right now, plugging in my shore power into the inverter will do. Then when I get some more time and motivation (not anytime soon with 2 young toddlers running around!), just go and do it the right way as it won't even take that much longer than this half baked solution (adding another ATS).

The only thing I want to do sometime soon is move all my battery connections to a nice Bus Bar and replace a few of the battery wires with thicker replacements. some of the factory ones and ones that came with the equipment are definitely too thin for the potential amps (Dont worry, still nothing under like 6ga).

I appreciate all the feedback here. It has helped me prevent some mistakes and ultimately guided me to the best outcome for the day!

[wa8yxm]

Just remember to disable the converter when on Inverter power.

[Veebyes]

I was in the same situation. My method of solving the problem was more basic.

I ran a short line from the generator input with a female plug at the end. From the inverter I ran a line from one of the output sockets with a male plug at the end.

The ATS is easily reached so when the inverter is used i simply plug it in. There is a remote switch inside to turn it on.

Unplugged there is no way to backfeed and fry the inverter.

[pianotuna]

Hi,

I chose manual plugs.

Never back feed.

What is the make and model of the inverter?

[Veebyes]

I was in the same situation. My method of solving the problem was more basic.

I ran a short line from the generator input with a female plug at the end. From the inverter I ran a line from one of the output sockets with a male plug at the end.

The ATS is easily reached so when the inverter is used i simply plug it in. There is a remote switch inside to turn it on.

Unplugged there is no way to backfeed and fry the inverter.

[time2roll]

A transfer switch to isolate the power sources is required.

What inverter are you installing? Some do not like to be wired in to an electrical system.

[1995brave]

Mine came with a second ATS built into the inverter. I'm in the process of changing over to Lifepo4 batteries and a 2000 watt inverter. I picked up a second ATS just for the inverter and wiring it right after the generator ATS. My Lithium charger will be wired at the same location.

[timelinex]

wnjj wrote:
How about a manual selector switch to choose between generator and inverter power like this one: https://www.amazon.com/VictorsHome-Changeover-Positions-Terminals-Universal/dp/B07MZ739CS/ref=sr_1_2...

Since each selection has different inputs and outputs, you would have to jump the outputs together when you connect them to downstream line.

Ordered a 63amp one that comes in a box. It will be here tomorrow.

Thanks!

[wnjj]

How about a manual selector switch to choose between generator and inverter power like this one: https://www.amazon.com/VictorsHome-Changeover-Positions-Terminals-Universal/dp/B07MZ739CS/ref=sr_1_2...

Since each selection has different inputs and outputs, you would have to jump the outputs together when you connect them to downstream line.

[Cptnvideo]

I'm in NW Surprise. Drove here yesterday from Payson. We went across Dynamite from Rio Verde to avoid Shea.
If you don't want the hassle with the 50 amp cord, you could pick up a 50 to 20 dog bone that plugs into the side of the RV, then hook up an ordinary extension cord to the inverter.

[wa8yxm]

If you are talking about wiring the Inverter in PARALLEL with the generator then yes there are several reasons not to do it... One of them is the Inverter may "Flame on" if you start the genny.

Now a betterway... Some inverters have power pass through (Built in transfer switch) wire the Generator to the IN and the out to the RV but that's still not a great idea.> WHY.

on your ATS the Generator rules.. If there is power on the Generator leds. then that's the selected power source.. and also the converter is live.

Putting the iverter there (The source of last resort) is goign to make it the preferred source plus it will be looping That is the converter is charging as the inverter is discharging and the result is swiftly dead batteries >

Best is to do it right.. Either a 2nd tansfer switch or even a manual transfer switch (you can get 30 ap DPDT or 3PDT center off transfer switches) or a small Generator transfer (manual) panel. (This is the best low cost option)

The inverter goes to the Generator leads on the transfer panel
You put only selected circuits on the transfer panel.. Like Bedroom Outlets.> kitchen outlets.. Microwave if the inverter is big enough. Entainerment circuits (TV/Radio/Sat receiver) Then you simply flip over to inverter as needed.

The linked panel is an example Just 4 14 amp circuits
Link for illistration only not recommending for or against this specific product

[Cptnvideo]

Frying the inverter is very possible as generator output would go into inverter output.
The output of the transfer switch goes to the AC breaker panel. I'm assuming the inverter you're buying has pass thru. If not, forget about the transfer switch.
PM me your phone number if you want to discuss.