Adding Solar to Bigfoot Roof

[Glenn Baglo]

My Coleman 40 watt panels ( made by SunForce ) plug into a hub ( takes several panels ), from the hub to controller and controller to alligator clips attached to battery terminals.
https://sunforceproducts.com/product...lar-panel-hub/

[ZachO]

That thing is serious! Thanks.

[ZachO]

Originally Posted by Franswa

Sikkaflex (?) is wonderful stuff...it keeps expanding for a while AFTER everything is tightened down....and stays flexible forever

One thing I've realized too late about sikaflex, though, is that eternabond won't stick to it. It will stick to dicor...but I used sikaflex. Oh well.

[Franswa]

never heard of that....


and I gotta say...you could spend half your life buying connectors and hubs yada yada....but in most of our applications we use 12V panels in parallel....so the voltage stays 12 volts


most if not all the "solar" connectors were developed to deal with the higher voltages that panels in series can produce....(you don't want to "play" with 600 volts!) Do you really want a connector you have to have a special tool to take apart ???? Not me.



I have three panels, 2 on the roof and one portable/deployable....the wires from the portable are spliced into the ones from the roof BEFORE the controller (controller is 30A....my three panels (40+30+40) would be lucky to produce 12A at high noon in the desert!)



all my wiring connections are either soldered...or made with wire nuts (inside trailer and taped) in instances where I think I might want to add to/modify later....


no blue smoke, still alive and happy with the results.
Have fun and carry on!

[gordon2]

Originally Posted by Franswa

...
most if not all the "solar" connectors were developed to deal with the higher voltages that panels in series can produce....(you don't want to "play" with 600 volts!) Do you really want a connector you have to have a special tool to take apart ???? Not me....

Well I assume you are referring to the MC4 connector. Yes, they are not meant to be routinely disconnected. But they are quite waterproof, and fairly easy to put on when you make custom cables. I use them for most of my solar connections but I use a marine trolling motor plug for the connection of the portable panels to the trailer, which is a temporary connection.

By the way I have found that if you use all Renogy MC4 connectors, then you dont usually need the tool to separate them. When I mixed brands, they fit too tight to remove by hand.. even though they are supposed to be a standard size.

[k corbin]

Originally Posted by ZachO

Well crap. Ok, thanks.

Looks like I'll probably be routing it inside then.

You could potentially install some lengths of RV molding that are used along blelly bands to cover the screws. It does come in white. There is a vinyl insert which slides into the metal band and that will give you a channel to put the wires inside of it. As it is meant to be used on the exterior and it is conformable to curves it might work just fine. You would want the narrowest version of it which I believe is 3/4".



But that seems like a lot more work than using a cable clam fitting on the roof to inside the trailer and then one of these to go back out the wall to the battery. I put in one of these thru the sidewall plug fittings so that I could use a portable panel now and again instead of being limited to the one on the roof.

https://www.amazon.com/Ruikarhop-Con...gateway&sr=8-5

[Civilguy]

Originally Posted by ZachO

Thanks.

I feel like this should be easier...but I guess I still know less than I think.

I want to wire this switch. I would have just spliced it into the + wire. But this diagram is throwing me off...This is for the solar panel cutoff.

Attachment 130542

Zach,

I have to take the challenge here. Imagine yourself as the happy little electron swimming from the positive pole of the battery toward the LOAD.

From the LOAD, you will return to the battery via the negative wire.

The LOAD could be most anything, but the basic fact is that you first need to get there to the LOAD from the positive terminal of the battery.

Well, if you look at the diagram, you will have to swim through the switch and make a U-turn to get to the LOAD.

The point is that after you make the U-turn at the switch and head in the opposite direction on the diagram, you are still on the positive pathway.

I guess that another way of looking at this is to say that the LOAD is what separates negative from positive.

Otherwise, a circuit is just a loop which is connected to both positive and negative.

Something has to separate the positive from the negative, right? Well, that something is the LOAD, not the change in direction at the switch.

(Now, I will also add here that the first person who posts that current and electrons actually flow from negative to positive earns the same respect I would offer the folks who would tell a kid that there is no Easter Bunny. Somehow, it's just more intuitive to say that current flows from the positive "hot" leg to ground or common or negative, so let's just keep it that way, okay?)

[gordon2]

Originally Posted by Civilguy

...
... Imagine yourself as the happy little electron swimming from the positive pole of the battery toward the LOAD.

From the LOAD, you will return to the battery via the negative wire.
..

Except that the happy little electrons actually swim from negative to positive.


But I have muddied the water enough here, and the direction is irrelevant to this discussion.

[ZachO]

I'll get into that...thanks

And thanks Karin, that looks like a perfect way to connect a portable.

Yeah Francois, being fairly new to all this, I tend to use the products made specifically for this application. But I remember that a lot of the old timers I play music with show up to jams in their campers and set out solar panels, most of which have a household style AC plug spliced into them. A lot of those guys used to work for the mine and have been around all kinds of industrial equipment and are used to just making things work. They don't need specialty connections.

Eternabond is a way to seal joints, but also a substitute for dicor and similar products. I laid some down over the feet of the panels for extra security, but since it won't stick to sikaflex, it's not doing as much as it could. I didn't completely coat the feet with sikaflex, just enough to cover the edges, so there's some bonding going on, but not ideal. I guess it's the same idea as your gorilla tape, except that it has a substance on the underside that sort of resembles butyl tape, but really, really sticky.

[ZachO]

Thanks Mike. All that makes sense. And if, in the diagram, we switched the position of the load and the switch, the diagram would make sense too (except that I guess I'd move the switch from negative to positive).

[WizWid]

Zach,

You are over-thinking this.

Cut the RED wire from the solar panel and put your switch there.
But hurry up - summer is almost over!

Jim

[gordon2]

Originally Posted by widgetwizard

Zach,

You are over-thinking this.

Cut the RED wire from the solar panel and put your switch there.

Maybe within a foot or so of the controller.. looks like thats an indoor only switch.

Originally Posted by widgetwizard

But hurry up - summer is almost over!

How true.. only two months until camping season begins!

[Civilguy]

Originally Posted by Civilguy

(Now, I will also add here that the first person who posts that current and electrons actually flow from negative to positive earns the same respect I would offer the folks who would tell a kid that there is no Easter Bunny. Somehow, it's just more intuitive to say that current flows from the positive "hot" leg to ground or common or negative, so let's just keep it that way, okay?)

Originally Posted by gordon2

Except that the happy little electrons actually swim from negative to positive.


But I have muddied the water enough here, and the direction is irrelevant to this discussion.

Gordon, don't hide, you won!

[Civilguy]

Originally Posted by ZachO

Thanks Mike. All that makes sense. And if, in the diagram, we switched the position of the load and the switch, the diagram would make sense too (except that I guess I'd move the switch from negative to positive).

Attachment 130552

Yep, looks good to me.

Maybe if they had colored the wires on the original, it would have been easier to see what's going on there. I had to stop and think about it the way it was drawn.

Actually, I like your approach of moving the positions of the load and the switch even better.

[Civilguy]

Originally Posted by widgetwizard

Cut the RED wire

Is this the movie scene where they have to disable the villain's bomb?!?

Wait, no, I think it's the GREEN wire!!!

No, wait, what if we're wrong?!?

[ZachO]

Originally Posted by widgetwizard

Zach,

You are over-thinking this.

No, I'm not over thinking it. I've known since before buying the switch that I'd install it on the positive wire and call it done. I wanted to be clear, though, since that diagram is confusing. Now we're just talking. I'd have this installed already except where I had to park my camper for the week (I'm house sitting) is really precarious and I don't want to move around in there a ton...so this will happen over the weekend once I'm back in the trailer.

I know what I'm going to do, I'm just annoyed at the diagram, so the discussion goes on.

It will be installed under the same dinette seat as the charge controller.

I'll still be in my camper full time till October, so there's plenty of time. Plus, with my new "battery monitor", I'm learning that I can easily go a full week with no charge, at least until I need to start running the heater. Good thing cause I just gave away my portable panels. Really happy to get them out of my way.

[Jim Bennett]

This is turning into a much tougher, more complicated job than my 4 (+2) panel setup.

Kidding aside, this is the drawing of what I did, except I did add a 30A fuse on the positive lead from the panels. I figured out my system by online research, asking a few questions on the Escape forum, then going over things with a tech at a local solar store. He suggested the breakers on either side of the MPPT panel for safety, but more for isolating parts of the system for working on it for any reason. They were quite cheap too.



Mind you, my trailer was busted into while stored and the portable panel stolen, so that needs replacing.

[ZachO]

Yes, only because I'm asking most of my questions here, rather than researching quietly by myself.

Too bad! I don't want to speak too soon, but we're lucky around here to have minimal crime.

I like how all your breakers are in the same place. That makes things nice and clean. I'll have a fuse at the battery and a switch under the dinette.