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 30 amp shore power hookups.
This diagram features:
- 3000W Inverter Charger
- 400+ Amp Hours of Battery Storage Capacity
- 400W-1200W Solar Array Capacity
- Alternator Charging
- Shore Power Charging/Passthrough
Not quite what you are looking for? Check out other system setups here: https://www.explorist.life/solarwiringdiagrams
Table of Contents
TABLE OF CONTENTS
History of Changes to this Page (Click to Expand)
Published: September 8, 2020 – Any changes made will be listed above.
HOW TO USE THIS PAGE – VIDEO
This orientation video will show you how to best use this page to build your DIY Camper Solar Setup. It’s a quick watch but I think it’s pretty important.
30 Amp OEM Camper Electrical Upgrade Wiring Diagram
30A Camper Solar Parts – Shopping List
The list below is a consolidated parts list for this entire system (Minus the solar charging leg, which is listed at the bottom of this blog post).
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.
30A Camper Solar Parts Detail
The section below will tell you where each of the parts from above fits into the wiring diagram. This is quite lengthy, but if you are having trouble seeing the diagram or just want more clarification that the diagram above doesn’t deliver, hopefully this will help:
Solar Charging Parts List & Wiring Diagrams
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)
Typical 30A RV OEM Wiring
Here is a quick look at how MOST stock OEM RV’s are wired:
- The diagram above shows the typical bare-bones OEM RV/Camper with 30A shore power service.
- Shore power flows into the breaker box, powering the breaker box protected by a 30A breaker where 120V AC power is then distributed to the various circuits.
- 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.
How to Integrate a DIY Camper Electrical Upgrade with the OEM Wiring
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 Victron Multiplus inverter charger. This charges the batteries which feeds the DC fuse block and allows 30A shore power passthrough to power the 120v appliances. You will take the 10/3 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 wire from the Multiplus Inverter/Charger to the AC Distribution panel should be replaced from the 10/3 OEM installed wire to a 6/3 wire and the 30A main breaker should be replaced with a 50A main breaker to accommodate for the additional capabilities of the Victron PowerAssist function.
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.
30A 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.
30A 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.
Cooper
Thursday 19th of May 2022
Hello Nate (and/or Others),
I am in dire need of some help. I have implemented this system in my 23ft travel trailer almost perfectly. There are only a few places where I deviated: * I did not implement the solar panels, the MPPT charge controller, or the system designed to charge from the alternator. The only things (aside from the batteries) that branch from my DC distributor are the cables to the bus bars and the cables to the Multiplus. *I did not implement the transfer switch from shore power as I only have 1 shore power inlet. *My system has 4 100Ah batteries instead of 6 like the diagram. *I put a 300A Blue Sea Systems Battery Switch in between the 400A ANL fuse and the distributor positive rail so I could disconnect the batteries from the system for maintenance and such (this seemed to be common in a lot of other builds). Otherwise, everything is exactly the same (same size lugs, same gauge cabling, same fuse ratings, etc.)
In almost all cases, the system works beautifully. If I'm not using the AC, I can stretch the batteries to over 2 days with my power consumption without being hooked to shore power. The problems start when I run the AC. When I run the AC (either with shore power hooked up or not) then the cables, especially the one running from the Blue Sea switch to the positive rail, get HOT. Hot hot. Like to the point I can't even touch it for more than a second. I've tested it several times, and each time it gets above about 80 degrees outside I have shut down the AC because I'm afraid the cables are going to start melting contacts or cause damage to the batteries somehow.
I'm trying to figure out a few things. 1. Is this normal? I read Nate's response to another user's comment that none of the cables should be too hot to touch, so I can't imagine this is normal.
2. What could cause this? I saw Nate (in the same response) say that it could be due to a bad crimp or a loose bolt on a lug somewhere. I checked every crimp with a pull test before installing them, I've checked every bolt and connection in the entire system and they are all solid. I do not know what else could cause it.
3. What methods could I use to diagnose the issue? I have just about every common tool I can think of at my disposal and the means to get any other common tools that I might need within a few days via various hardware stores.
Any help from anyone would be greatly appreciated. It's touching 90 today in South Dakota, and not having any AC is KILLER.
Amon Barker
Monday 25th of April 2022
Nate thanks for the great info! I am installing a very similar setup to this wiring diagram on my Cirrus 620 camper and had a few questions.
1.) I plan on installing the Victron Cerbo GX and GX 50 Touch for monitoring. I was debating between the Victron Smart Shunt with BMV-712 or the Lynx Shunt without BMV-12. Do you have a recommendation for this setup?
2.) I am planning on using the Victron Inverter/Charger 3000. I have been deciding which batteries to use. I see that 400ah+ is recommended for this setup but I have been looking into the Lithionics 320 Ah battery as it is the perfect size for the battery compartment in the Cirrus 620 camper and can heat itself. From what I can tell the Lithionics user manual lists the battery as working with the Victron 3000. Do you think this battery will work with the inverter or do you think I should go with 400ah?
Nate Yarbrough
Sunday 15th of May 2022
1: Either will be good given use of the Cerbo GX.
2: I recommend going with 400Ah or more of Battle Born Batteries.
Sunny Days
Thursday 21st of April 2022
Say Nate! I've been trolling through your material. Fantastic stuff. Really. I downloaded your wiring diagrams for both the 30A RV retrofit and the one has a 3000w Inverter. I'm looking at trying to pull off a 30A retrofit with a 3000W inverter, two 300Ah batteries, and six 240W panels. (The three parallel strings of two panels in series total 54.16V x 32.13A = 1740W.) On your 30A retro diagram there's 6-3 wire going from the Multiplus to a 30A fuse in the distribution panel. In the 3000W diagram there's a 6-3 wire going from the Multiplus to a 50A fuse. My unit has a 30A oem fuse, of course. Am I ok to stick with what is there, or do I need to upgrade to 50A? If 30A is ok, is it alright to keep and use the 10-3 there, instead of upgrading to the 6-3 wire? (I ask because the retrofit will be a good bit easier and a little cheaper using the 10-3 that is already installed.) Thanks!
Eric
Sunday 3rd of April 2022
Hi Nate, thanks for developing these plans and videos. With your guidance I’ve been working on an upgrade to my Micro Minnie and am struggling to understand how to connect all the 12v accessories that run off the OEM battery. Currently the jacks, slide, battery etc run to a ground-to-frame bus and the positive battery connects to 2 auto reset circuit breakers. I realize not all travel trailer are alike, but I’m curious if there’s a more detailed resource for connecting a Lynx distribution and bypassing the original battery with bus bars? Thanks in advance for any insight!
Martin
Thursday 24th of March 2022
Hi,
Just a quick question: Is it better to upgrade the OEM converter of the RV to a converter that will charge Lithium battery or to buy a 3000W inverter/charger.
thanks