I have a 28’ TT. Front bedroom and my main setup batteries charge controller and inverter/charger live underneath the bed. My question is my main fuse panel for the trailer is in the very rear , if I installed another charge controller near that panel and a few panels on the rear of the unoccupied rear of the trailer roof could I connect directly to the fuse panel or should I have a new run to the batteries in the front of the trailer?
RV wiring question.
- Thread starter Schorchy
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FilterGuy
Solar Engineering Consultant - EG4 and Consumers
It would be good to provide a circuit diagram. However, if I am following the description correctly, I don't see why you could not tie in at the fuse panel.
FilterGuy
Solar Engineering Consultant - EG4 and Consumers
Yes. The wiring would need to be large enough to support the set-up from both a safety and functionality (Voltage Drop) point of view.
A few mitigating points:
* Presumably (Hopefully?) the wires between the battery and the load center are already fairly large in order to be able supply the loads.
* If the charger has an accumulation phase, the voltage drop will go down as the current goes down. Consequently, the difference in state of charge due to the voltage drop may not be very large at the end of the accumulation phase .
* Even if the added 'back' panels don't get them to the full state of charge desired, they will help charge the system for a net benefit in production capacity.
John Frum
Tell me your problems
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RV wiring is notoriously frugal.
I suggest running the biggest wire that will fit the distribution center mechanical lugs.
I would locate the MPPT as close to the batteries as possible to leverage the higher voltage created by the panels. The voltage has to get to the batteries one way or the other. Best to make the long run a wire appropriate to the length and voltage generated by your panels.
It really depends on the amperage you expect from your controller. The wires from the fuse box to the original battery compartment is usually 6 gauge. If you are running a 30amp output you are going to have noticeable voltage drop. If you are adding another 10 amps you will have a hard time detecting any loss.
chrisski
Solar Boondocker
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I would connect both SCCs at a busbar at a point that makes for me, for me which is the battery.
I would not wire through the panel unless I was absolutely sure how that 30 amps of how current gets to the battery. My trailer came with a charger that only did 10 amps of charging so without knowing the entire pathway has 10 gauge or thicker wire, I would not connect a 30 amp SCC.
Some other things that would let me connect it to the fuse box if the wiring would handle the charge to the battery would mostly be impossible to wire otherwise. I hate removing wall panels and the plastic under bottom of the RV to access wires, so at some point I’d give up on the wiring
I would not wire through the panel unless I was absolutely sure how that 30 amps of how current gets to the battery. My trailer came with a charger that only did 10 amps of charging so without knowing the entire pathway has 10 gauge or thicker wire, I would not connect a 30 amp SCC.
Some other things that would let me connect it to the fuse box if the wiring would handle the charge to the battery would mostly be impossible to wire otherwise. I hate removing wall panels and the plastic under bottom of the RV to access wires, so at some point I’d give up on the wiring
FilterGuy
Solar Engineering Consultant - EG4 and Consumers
All of the above is correct. Assuming you are not driving more current than the wire can safely handle it will work. There may be ways of making it work better with heavier wires or different location of the charge controller. How much better is hard to determine with the info provided.
Another vote for putting the solar charge controller in the front compartment.
The loads coming out of the main distribution panel are low amperage. The amperage between the solar charge controller and the battery is going to be high, maybe 50 amps depending on what panels you put up. Voltage loss over 25' at 50 amps is a lot worse than the voltage loss over 25' at only 5 amps.
The loads coming out of the main distribution panel are low amperage. The amperage between the solar charge controller and the battery is going to be high, maybe 50 amps depending on what panels you put up. Voltage loss over 25' at 50 amps is a lot worse than the voltage loss over 25' at only 5 amps.
Whinny
Solar Enthusiast
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Seeing that the loads at the fuse panel will mitigate some of the current going to the batteries I see no issue with your proposal. As mentioned it is probably #6 feeding the panel, so some drop may occur-depending on the size of the array. Mock it up and measure, that's the only way to be sure.
