Looking to add a DC-to-AC Inverter to my 337RLS

**DohMan** · 05-02-2022, 12:36 PM

Looking to add an Inverter to my 337RLS. It's factory prepped for one and I want to make sure I have an understanding of how it's wired. It has a orange piece of Romex cabling that comes into the compartment inside a section of conduit that is labelled INVERTER PREPPED. The cable runs out of the conduit for about 12 to 18 inches then makes a loop and headS back into it. This makes sense if it is the insert point for the Inverter. If I were to cut the cable in half at this point, one half would be the hot side with 120 AC coming from the breaker/distribution panel, the other have would then be connected to the outlets that are powered by the panel. The hot end would be the AC in for the Inverter, the other end would be the AC out of the inverter to the outlets and of course two leads to the battery for the 12VDC input. Is my thinking correct??

**A.Texas.Yankee** · 05-02-2022, 10:47 PM

Yes, you're thinking is correct. But is the entire panel pre-wired to run off inverter, or a subpanel with only certain loads would be my question.

Full-time Traveling Family ,'21 Momentum 395MS-R, '21 F450 King, 2000watts solar, Dual Victron MP-II 12/3000 2 x 120v, 1220ah LiFePo4

**DohMan** · 05-03-2022, 06:26 AM

Originally Posted by A.Texas.Yankee

Yes, you're thinking is correct. But is the entire panel pre-wired to run off inverter, or a subpanel with only certain loads would be my question.

Full-time Traveling Family ,'21 Momentum 395MS-R, '21 F450 King, 2000watts solar, Dual Victron MP-II 12/3000 2 x 120v, 1220ah LiFePo4

I'm going to have to trace out or "tone out" the cable that would be the output from the inverter. Since this is a 50A system it has two hot legs in the distribution panel. I'm assuming that this output from the inverter would power one of the legs and the associated outlets connected to the leg. I know some manufacturers mark the outlets that are inverter capable. Probably should read the manual LOL!

**KDRunner** · 06-04-2023, 09:30 AM

Curious what year yours is. Mines 2021 and I have re wired everything and installed Multiplus II. Didn't see any prep for inverter in mine. Just had the solar prep wiring which I used. Hope you figure it out.

**DohMan** · 06-04-2023, 10:31 AM

2022. AC circuit breaker panel is labeled for an inverter in and out and I have wires located in the front storage in the ceiling "C" channel labeled Inverter. You cut the wire and insert the inverter. You need an inverter with a transfer switch either auto or manual. You have to determine which half of the wire is AC input to the inverter and which is inverter AC out which is fairly straight forward. Need to update my house battery first. Going to one or possibly two 100A lithiums and then possibly two more solar panels.

**KDRunner** · 06-04-2023, 01:09 PM

Nice upgrade from my 2021. I put multiplus II in front storage (too tall to fit in pass through, batteries in pass through) and had to run a new AC line from the inlet to the inverter and from inverter to panel box. Wasn't too difficult. Power supply that came in camper I just unplugged and disconnected wiring. Went with 6 battleborns. Lithium definitely way to go, just don't over expect what you'll get from solar. Think it out well so you don't end up doing it over again wanting more than what you put in first round.

**ggjarhead** · 07-13-2023, 06:28 AM

KDRunner- I have a 2020 337. did you add a sub panel to your system? My distribution panel is full and also not inverter prepped.

**COGrandDes** · 07-13-2023, 08:27 AM

Originally Posted by DohMan

Looking to add an Inverter to my 337RLS. It's factory prepped for one and I want to make sure I have an understanding of how it's wired. It has a orange piece of Romex cabling that comes into the compartment inside a section of conduit that is labelled INVERTER PREPPED. The cable runs out of the conduit for about 12 to 18 inches then makes a loop and headS back into it. This makes sense if it is the insert point for the Inverter. If I were to cut the cable in half at this point, one half would be the hot side with 120 AC coming from the breaker/distribution panel, the other have would then be connected to the outlets that are powered by the panel. The hot end would be the AC in for the Inverter, the other end would be the AC out of the inverter to the outlets and of course two leads to the battery for the 12VDC input. Is my thinking correct??

The inverter prep on my 303RLS powers everything in the AC panel except for the two AC units and the fireplace. I added a 2K watt inverter for all the powered things and am quite happy. I'm guessing yours is wired the same.

**KDRunner** · 10-07-2023, 07:03 PM

Originally Posted by ggjarhead

KDRunner- I have a 2020 337. did you add a sub panel to your system? My distribution panel is full and also not inverter prepped.

Sorry, I never saw your question. No I did not. Explorist.life has some really helpful wiring diagrams and videos. Your panel doesn't need to be inverter prepped. With the Victron multiplus II, just replace your main power coming from inlet to panel to inlet to multiplus and multiplus to panel.