This blog post is going to teach you how to add an Inverter, Alternator charging via DC-DC Charger, and Solar charging to your OEM camper or RV that came factory installed with 50 amp shore power hookups.
This setup will allow for 120V appliances/devices to run on shore, generator, OR battery power. 240V appliances will run on Shore/Generator only (and will need a 120V/240V compatible breaker box (Not shown below).
This diagram features:
- 3000W Inverter Charger
- 400+ Amp Hours of Battery Storage Capacity
- 400W-1200W Solar Array Capacity
- Alternator Charging
- Shore Power Charging/Passthrough
Table of Contents
50 Amp OEM Camper Electrical Upgrade Wiring Diagram
CLICK HERE TO PURCHASE THE HI-RES PRINTABLE PDF OF THIS DIAGRAM
50A Camper – Inverter w/ Solar & Alternator Charging Upgrade Shopping List
The following list will show you 98% of the items you need to install this system on your camper. If you need clarification on where something goes, please refer to the ‘Detailed Parts List’ below this consolidated shopping list. Also, you will need to refer to the solar array wiring diagrams at the bottom to add the appropriate solar array parts to your system below.
A NOTE ABOUT QUANTITIES
For the ‘Quantities’ in the below shopping list, each singular component is listed a quanty per each, wire is listed a quantity of feet, and heat shrink is listed as qty 1 = 2.25″.
For Example:
Qty 1 – Inverter Charger means you need to purchase 1 Inverter Charger
Qty 3 – 4/0 Wire means you need 3 feet of 4/0 wire. This may mean you need to buy 5ft from the product page
Qty 5 heat shrink means you need 5 pieces of 2.25″ heat shrink. This means you’ll need 5 x 2.25″ pieces of heat shrink for a total of 11.25″ of heat shrink.
Qty 8 – 2/0 x 5/16″ Wire lugs means you need 8 wire lugs… not 8 packs of wire lugs.
50A Camper – Inverter w/ Solar & Alternator Charging Upgrade Parts Detail
Choosing your Solar Panels & Charge Controller
The following section provides you with several different options for solar charging. The above parts list can remain completely unchanged and the diagram above can remain mostly unchanged except for the alterations noted by the diagrams below, but whatever solar array setup you choose below for your needs, these parts will need to be added to your shopping list. These are broken up by total solar wattage. As a general rule, you want to have twice as many watts of solar as you do amp hours of batteries. So, 300Ah Batteries = 600W solar. 400Ah Batteries = 800W solar. 600Ah Batteries = 1200W of solar. This is just a rule of thumb. Not a law.
400 Watts – 4x100W Solar Panels – 12V Battery Bank (Click to Expand)
600 Watts – 6x100W Solar Panels – 12V Battery Bank (Click to Expand)
600 Watts – 3x200W Solar Panels- 12V Battery Bank (Click to Expand)
800 Watts – 4x200W Solar Panels- 12V Battery Bank (Click to Expand)
1000 Watts – 5x200W Solar Panels- 12V Battery Bank (Click to Expand)
1200 Watts – 4x300W Solar Panels- 12V Battery Bank (Click to Expand)
How to Integrate a DIY Camper Electrical Upgrade with the OEM Wiring
The following section of this blog post will teach you how to integrate the wiring diagram and parts list above with your RV’s OEM electrical system.
Here is how the typical camper with 50A shore power hookups is wired:
- The diagram above shows the typical bare-bones OEM RV/Camper with 50A shore power service.
- Shore power flows into the breaker box, powering the breaker box protected by a 50A breaker where 240v power is divided up into 2 legs of 120V power to power both sides of a breaker box
- One circuit is generally the Converter. The converter is usually built into the same enclosure that houses the breaker box (as shown) but is sometimes external. Either way, it’s wired in the same method.
- The converter converts the 120V AC power to 12V DC power which feeds the DC Fuse Block which powers the various DC devices around the camper (Lights, Fans, Etc..).
- From there, a positive and negative wire continues on to the house battery bank; usually two 12v batteries wired in parallel. These wires charge the batteries from shore power, and allow 12v devices to run when not connected to shore power.
- At the batteries, there are usually 2+ additional positive and negative wires heading off under the RV somewhere that are going to power additional DC circuits around the camper. These may be slide-outs, powered leveling jacks, and other ‘chassis’ items like that. These wires will likely have fuses in line to protect these wires coming from the battery.
- One of these wires is also likely the wire coming from the alternator to charge the house battery bank.
When the camper is NOT plugged in to shore power, all of the 12V DC appliances will run due to them still being connected to the batteries, but the 120V AC appliances will NOT operate because the converter is a one-way-street and will not convert 12V DC back to 120V AC. The charging from alternator is typically very slow (less than 10 amps) and should, generally, not be relied on to provide adequate power for recharging deeply depleted house battery banks.
In addition to wiring the components together, here is a breakdown of how the flow of power to the above diagram works.
WIRING THE INVERTER/CHARGER To Shore Power.
When connected to shore power or generator, power flows from shore power (or generator) to the inverter charger. This charges the batteries which feeds the DC fuse block and allows 50A shore power passthrough to power the 120v appliances. You will take the 6/4 wire that goes from the shore power inlet to the back of the AC distribution panel and instead, run that wire from the shore power inlet to the input of the Victron Multiplus.
Wiring the Inverter/Charger AC Distribution Panel
The 6/4 Wire from the AC Out of the Inverter/Charger will go to the same place that was just mentioned in the above step.
Wiring the Solar Panel Array to your Camper Electrical System
When charging from solar, the solar panels & charge controller charge the batteries. The batteries are connected to the DC fuse block allowing use of the 12v devices around the camper. The Inverter takes the 12V DC power stored in the batteries and converts it to 120V AC power to power the 120V AC items around the camper.
Replacing Stock Camper Batteries with Busbars
A positive and negative busbar take the place of the stock batteries in the stock battery location (assuming that upgrading batteries means you will not be able to store your new battery bank in the stock location). From the Lynx Distributor, power flows to these two busbars where power is then sent to all of the OEM installed components like the DC distribution block, power jacks, slides, etc.
50A Camper Converter
The OEM installed converter must be completely disconnected. It can remain installed, but the wires must be disconnected from both the AC and DC side of the power distribution center. These wires can usually be bundled up and stuffed next to the converter.
50A Camper Alternator Charging
You will likely have a wire charging your OEM batteries from the alternator. This wire will likely be somewhere in the 12 AWG range. This will either run directly from your starting battery isolator if this is a motorhome or from your 7-pin connector if this is a trailer. This needs to be disconnected completely. This diagram uses a 30A DC-DC Charger and the OEM installed wire will be too small. The 6 AWG wire in the diagram will take the place of the OEM wire you are to remove. In the case of a trailer, 6 AWG wire will need to be run all the way to the truck starting battery if alternator charging via DC-DC Charger is desired and disconnected by the hitch by means of an Anderson connector. If you do not wish to charge via the Alternator… this entire leg of charging can be omitted without ill effects.
Doug
Thursday 22nd of September 2022
Hi Nate (and Steph!). Working on a 50A Airstream. I've got a stock inverter. I can see wires that I "think" come directly from the OEM batteries. And I can see a single Romex coming out of the inverter that I "think" go to the one circuit breaker in the AC Distribution Panel that powers all the inverted outlets. These wires disappear under the floor within a foot of the inverter itself. And then there's another wire with a standard three-prong plug that appears to be manufactured into the inverter, which is plugged into a hidden "household-type" outlet. Question: What might that mystery wire/plug be???? Or... why would an inverter be powered with 120v?
And... are my conclusions correct?>>>
1. I don't care about the inverter because "inverted outlets" are already hooked to the AC Distribution Panel and, once wired to the Multiplus II, will be powered (just like when previously plugged into shore power). 2. I can disconnect and cap the 12v wires, leaving them lay where they are. 3. I can unplug the mystery wire plugged into the hidden outlet. 4. I can remove the inverter altogether, or leave it where it is, disconnected.
Thanks for any light you can shed.
Wes
Tuesday 20th of September 2022
Thank you for sharing your knowledge. I am starting this upgrade as well and I have a question related to all the OEM wiring that is currently in place. I know it's not done well and there are many wires stacked on studs and I would like to clean this up. Is there a product that I could buy to individually connect the existing black/red wires to instead of leaving them jumbled together? These are things that are NOT connected after the battery disconnect switch that have to work all the time. I'd like to trace & label the slides, jacks, etc. and have them in a dedicated place. If something exists, what would I need to do in order to ensure the battery disconnect switch doesn't disconnect them and can it be done in a way such that the Victron BMV-712 can still monitor those loads?
Martin
Saturday 10th of September 2022
Hey Nate, great website – very informative. I started out doing my DIY solar upgrade in stages – initially 6*100W Renogy panels with 60A MPPT charge controller, secondly 3000W Renogy inverter/charger, and lastly, the 4*170Ah LiFe batteries (yet to be purchased). I have a fifth wheel with 50A shore power and a 5500W generator. I can easily run the AC’s when boondocking. I’m investigating how to wire the shore power through to the inverter and back to the AC distribution panel. I’m getting very confused as to which of your wiring diagrams I am to purchase/use as it appears your only wiring diagram that uses the Renogy products is for a 30A shore power supply with 3 core wires (L/N/Pe) to and from the inverter, and your other diagrams are for Magnum or Victron Multiplus II 3000-2*120V inverters that take a 4 core wire (L1/L2/N/Pe) 50A supply. The latter diagrams are self explanatory and extends the current 50A cable from the shore/generator transfer switch to the inverter and back to the AC distribution panel - simple. But these diagrams are for a 4 core wire 2*120V 50A supply to a 4 terminal inverter – and they also allow for a full 50A bypass. However, the Renogy inverter only has 3 terminals (L/N/Pe). I’d assume one circuit would go to the inverter and the remaining circuit be wired directly into the AC distribution panel. Then, if I am not mistaken, I would have one side of the AC distribution panel having 120V – 50A and the other side of the panel having 120V – 25A (i.e. 3000W/120V) returning from the inverter. Is this the correct way to wire a 50A shore power supply into a 3 terminal inverter? Do you have a wiring diagram that shows how to wire a 50A 4 core wire shore power supply into a 3 terminal inverter? Any finally, is the reduction in overall power going to limit the use of appliances and the AC units under shore, generator or inverter power as there is actually less available wattage - down theoretically 25%?
Brent Livingston
Friday 9th of September 2022
Nate, thanks for all the information and diagrams. Reviewing this blog and the 50A OEM RV Retrofit diagram I purchased, I see the blog indicates "Lynx Distributor to Busbars" as 2 AWG wire in the product list. Looking at the diagram I see 6 AWG between the Lynx and Busbars. Can you clarify that for me? Thanks again for all your hard work and helpful information. Brent Livingston
Mike
Tuesday 16th of August 2022
12v vs 48v. Curious why all the write-ups are for 12v systems. Why not get a 48v battery? If 12v is really needed, just get another converter 48v dc - 12v dc.