Class C motorhome install

[Browneye]

I moved the generator starting lead from house to chassis. It doesn’t do any 12v charging anyway. Still supplies the same 120 volts for those circuits - AC, micro, gas fridge on AC, and outlets. I added dedicated outlets for the inverter. Doing it again I would tie into some or all AC circuits with a transfer switch. But it works well enough. We use the inverter for electronics charging - phones and computers, TV, and ebike batteries. The coach came with a small inverter for TV and surround sound. TV changed out for led flat panel.

Converter charger unit replaced with a Meanwell NPB-series charger for lfp house. I added a switched outlet for it - only gets turned on when needed if plugged into shorepower or run the generator. Solar pretty well recharges every day, and Orion charges when we drive.

Added a solar generator - Delta Mini for high watt appliances - hair drier, coffee maker, air fryer, etc. even a 1kW inverter won’t power those appliances, most draw more than a 1000 watts.

For air conditioning the gen runs, we plug in, or we leave. ?

12V use is 50 to 100Ah overnight on battery. The furnace blower is now the big draw, all lighting converted to led. RV appliances are LPG, water heater, stove/oven, fridge, furnace.

 

[Factsmanmp]

I eliminated the isolating solenoid and used the ignition lead for the Victron Orion dc2dc charger. Dash switch disabled.
Could join house and chassis with jumper cables for a starting battery failure. To prevent that ever happening I installed parallel starting batteries and their own 100W panel and charge controller. They live where the old lead house batteries were in the “outside” tray.

my house batteries are under my step too. When you said isolating solenoid is that the same as a Bi directional isolator? I also have a Continuous Duty Solenoid….. what is that for? I’m hoping I have a cable coming from the starter battery/alternator in this compartment that I can use for my dc to dc charger like you show in your picture.

 

[Browneye]

Mine had two solenoids - the isolator/combiner and the master on/off.

Continuous duty sounds like master switch.

 

[Geokilroy]

Please forgive my newbie questions. I did research before posting.

I have a Class C Motorhome from 2003 with Deep Cycle LDA batteries. I am starting the process of converting to Lithium but every time I think I understand it, another issue pops up.

I modified the diagram on the Renogy page, does this look correct?
View attachment 122871
I currently have:
2 100ah 12v Amperetime (LiTime) Lithium batteries
1 Renogy DCC30S 12V 30A Dual Input DC-DC On-Board Battery Charger with MPPT
1 PowerDrive 1000W Bluetooth Pure Sine Wave Power

Stuff to add according to my diagram unless I am wrong. I realize Solar addition can happen after.

300-400 Watt solar panels
Converter/Charger replacement since the current one I assume won't work with lithium batteries.

I am assuming there is already an automatic transfer switch between the on board generator and shore power prior to the converter/charger. Is that a correct assumption?

Does the on board Onan generator use the house batteries to start? Will the Lipo batteries be able to do that? I don't use the generator much, but would like to keep it as an option.

Just a question. Is the neg wire from the panels also connected to ground? Shouldn't it go directly to charge controller input like the pos wire and then controller neg output to ground? Isolating the solar panel with the controller only and not grounding the panels to his rig.

 

[Factsmanmp]

Mine had two solenoids - the isolator/combiner and the master on/off.

Continuous duty sounds like master switch.

I wonder if Fleetwood has a diagram.

 

[Browneye]

Winnebago does, but I have difficulty reading them. LOL

 

[eXodus]

I moved the generator starting lead from house to chassis. It doesn’t do any 12v charging anyway.

I was looking how to upgrade the 12V house batteries on my Motorhome to LFP, but was stuck with the generator starting question.

This is a great simple idea.

 

[Browneye]

I was looking how to upgrade the 12V house batteries on my Motorhome to LFP, but was stuck with the generator starting question.

This is a great simple idea.

Identify the positive cable from the gen, it will likely be in the general area where all the cable arrive at the solenoids and batteries, and move the terminal to a post or circuit for the chassis/starting battery. An existing connector post may even have room on it. Or install a connector bus with posts.

My two circuits are now completely separate - hose and chassis. Chassis batteries got their own 100w Solar panel and charge controller. Doing it again I would get a TRIKLSTART maintainer. The good news is my starting batteries are always topped up. If you store under cover then all bets are off. ?

 

[eXodus]

In the end I'm going to have 3 different systems.

12V Chassis Group starter battery (charged with voltage sensing relay from house, or alternator)

12V House 2x 100AH AGM (100W Solar PWM, Converter or Alternator charging)

24V 10kWh LFP 900W Solar 3000W AIO Inverter (able to charge the 12V house over the Converter)

Essentially I have it configured that it's all one way - the large system may charge the smaller batteries - but can not discharge the chassis.

MY AGMs are getting up in age and are heavy, I think I can replace the 2x 60lbs AGM with One 20lbs 12V 100AH LFP. But so far haven't found a BSM which would tolerate the inrush current of the generator start. But you gave me that idea - that I don't have to