Solar Suitcase & OEM system?

[chin_k]

FWIW, I will be moving my solar controller near the LVD, and may replace LVD completely. The voltage drop from the controller to the batteries will make the batteries not able to be charged optimally. When it come to battery chemistry, every millivolt make a difference. The voltage drop from the panel)s) to the solar controller is not as bad, relatively. I am not going to spend the money to get a controller with precise charging algorithm, and have all the parameters off due to skinny wiring.

As mentioned, solar panel technology has changed a lot in past two decades, and the cost also dropped dramatically. The 50W panel back then was the top of the line, but there are a lot better ones nowadays.

[HoosierB]

... and may replace LVD completely.

chin_k, what is the advantage of this and how is it done?

[chin_k]

Have not decided on the model, but a few of the solar controllers have the LVD built-in, and I would like to take this opportunity to combine the original LVD with the solar controller. Make the controller closer to the batteries, so better efficiency too.

I wish someone combined the charger/inverter/converter/solar controller in one package, but so far, I have not come across a good all-in-one alternative. The easier one is the LVD+solar controller.

A few solar controllers have the feature of switching the load on/off, which essentially is what the switch above the driver seat is for. The controller also automatically disconnect the load from the batteries when the voltage is below certain level, so both of these functions are what the LVD is doing. The tricky thing is that I need to decided on if I want to go with MPPT this time (or later), and make sure the controller is switching on the positive wire. I used a controller a few years ago for a project, and it was negative switching, so I have put a transistor on the circuit to get it to work. For my RV, I would not want to do that.

Right now, I am still working on upgrading the wiring from the LVD to the brown box. I need this upgrade for the LVD/controller to work, since there will be a lot more amp of current among the components.

[HoosierB]

Right now, I am still working on upgrading the wiring from the LVD to the brown box. I need this upgrade for the LVD/controller to work, since there will be a lot more amp of current among the components.

I'm planning the same wiring upgrade by running a PVC conduit along the sofa wood support against the wall which will allow a feed for wire from the brown box to the LVD as well as a 12/2 wire for a future hookup of a combo water heater. What AWG are you using for the LVD run?

[chin_k]

I ordered 4 AWG Ancor marine cable for the section between the LVD and the brown box. The reason I am using such large wire is because I want to let it carry 45 Amp (original, I will have a slightly larger inverter, but that's different story) to the batteries, without much voltage drop, from the charger. I will use the existing skinny wire to power the the accessories in the brown box from the LVD (or the new, to-be-determined controller), since the accessories do not care if it is a few millivolts off, since they are all just need to run on ~12 V DC. When plugged in to shore power, the "inverter" will power the accessory directly via the 4 AWG wire to the LVD, then back to the brown box via the skinny wire. If you are staying with 45 A, you should be able to get away with 6 AWG, but I need to run the number to confirm.

I do care about efficiency is because unlike the original setup, the charger I have is 3 stage version, just like your solar controller. If I let the voltage drop get the voltage off, mine as well keep the old technology.

[danesk]

Greetings, and thanks for the good info in this thread.

I will be installing two 100 watt panels on my Concourse roof - I've removed the old panel and the TV antenna. The new charge controller is a 20W MPPT. Based on various solar wiring charts, my voltage loss from the new controller to the batteries will be approx. 4% using the original 12 AWG wiring. I would love to replace that with 10 AWG wire run in an enclosure up the inside of the Concourse and into the overhead storage area to the controller, but can't figure where to drill a hole up through the existing battery compartment to safely route the wires inside.

Has anyone does this or something similar? I can submit some photos of my specific situation if that would help.

I perhaps can live with that 4% loss, but I know each millivolt is important.

Thanks for your time.

Dan

[Blue~Go]

Dan,

You are smart to be questioning. 4% voltage drop is completely unacceptable in a solar charging system (well, any charging system). Here is why I say that: So your batteries want (say) 14.4 volts to charge in absorb stage. It's important that that be accurate. Take away 4% and you 13.8 volts. That means your batteries will never get past bulk stage which is bad for them. They will die prematurely. IMO there is just no sense in going through all of the work to install a solar system and then ruin it all with a "leaky hose."

So for starters, you want to put the solar charge controller (I'm assuming that's a 20 amp MPPT, good choice) as close to the batteries as possible. In other words, forget the original location. Chinook was forward thinking with solar, but we've come a long way since then.

Are you putting the panels on the passenger side? If so I would use a cable clam near the forward end of the roof, and run the wires into the forward cabinet over the table. From there there is a not-too-difficult path across the entertainment area to the pillar and down. Better and easier would be to have them on the driver's side, but maybe you have other things there.

Next are you running them in series or parallel? I run two 100 watt panels so I am familiar with the output. Actually, I will stop now until you respond because no sense going into a bunch of detail since I don't know which side or etc. But no matter what you do, I would absolutely not use that 12 AWG wire. That's like having a burly tow vehicle, and a big sturdy trailer, and then hitching them together with string. Defeats the purpose.

So if you respond we can take it from there. You will love the 200 watts. It's not the biggest possible system but it's a nice, manageable size and will give you lots of charging.

If you could also say what type of batteries you have (flooded cell, AGM, LiFeP0, etc.) then we could talk about temp comp considerations.

BG

[Blue~Go]

PS: No need to drill a hole up through the battery compartment. At least on all I've seen, Chinook runs the wires out the forward side of the compartment, then up through holes in the floor that come out inside the pillar. Those spots are easier to reach!

[danesk]

Blue~Go,

Thank you very much for the excellent info and advice! Thanks to your explanation, I am now committed to using the 10 ga. wire supplied by Renogy from controller to battery...maybe even 8 ga. to further reduce voltage drop. Here are a few details about my installation:

I removed the TV antenna and covered the large hole with 1/8" aluminum/screws/dicor so there may be just enough length to mount both panels on the driver side - it will be close. Otherwise I will mount one on passenger side where the original panel had been installed. I will be using the supplied Renogy mounting hardware with added 3M 4950 tape and plenty of dicor.

On the inside, a monitor had been installed where the original TV was...when traveling/camping, the last thing we need is a movie, so that can come out to provide room for the new controller and perhaps a small bookshelf.

Since a parallel connection would provide more amperage, I believe that is the best way to go...?

Batteries (2) are 100AH AGM deep cycle from Windy Nation - parallel connection.

I think my main question and likely most difficult task will be to run the new wire from battery up. I had read in a similar thread on this forum about the difficulty removing the pillar...was that your project? (I believe the sofa had been removed in that project) So I had thought of running the wire, encased in suitable enclosure up the inside and then into the overhead area to the controller. But if pillar can be removed without too much work, I will do that. I wonder how best to push the new wire through the existing opening in battery compartment, through floor and then up.

(Many years ago I helped an electrician rewire an old building by pulling the new wire through with the old wire...with all the tight turns, don't think this would be possible in the Chinook).

Any thoughts on installing the new wires will certainly help. Obviously you have "been there, done that" and your advice is most appreciated.

[chin_k]

I think the sofa can be removed with just a few bolts. You just need to remove the top portion, not taking the entire sofa off. I am not even sure if you have to deal with the sofa.... where did you read that to work on the pillar, you have to remove the sofa? I think Flame or 69camaro may have to do that a few months ago...