Solar Panels and Holes in the Roof

capewoods

I'm getting closer to implementing my solar project on my T@B trailer and I'm going to be starting with two 100w panels.  Because my trailer is a clamshell and in order to capture better sun, the panels will be located on either side of the roof pretty far forward.  I'm debating how best to get the wires inside.  One option would be to join the respective positive and negative leads (I'm running in parallel) on the roof using MC4 Y connectors and then take only a single positive and single negative wire either through the roof or off the roof and through a side hole where I currently have a radio antenna attached.  This, however does seem a bit messy on the roof and even with industrial tape over things, I'm worried that it will look bad and may result in windstream whistle.

Another alternative would be to take each of the leads through its own hole in the roof into the cabinet dead space below and join wires there.  This means more holes, but a much cleaner exterior and these looked like a good option for accomplishing the hole without risk of leaking:

http://www.westmarine.com/buy/blue-sea-systems--side-entry-cableclam-with-stainless-steel-dress-cap--14982532?cm_mmc=PS-_-Google-_-Shopping_PLAs-_-14982532&adpos=1o1&creative=54601694764&device=c&matchtype=&network=g&gclid=CjwKEAjwgcipBRDgxK_3ztrBty8SJACRuv4dp4PvOGltGDYHwjw26IvltnWNUexiiEWU686QvtbcHxoCkM7w_wcB

Would love to hear what people think.  Thanks in advance for your thoughts.

Michigan_Mike

I think your dual wire entry idea sounds great and I like the entry caps too as they create a clean entry point into your trailer.  It sounds like you've put some thought in this too via consideration of wind resistance and the subsequent whistling you get from various protrusions on vehicles.  And as luck would have it, here is another member who recently installed some panels on the roof.  

The biggest hurdle or the major consideration is keeping the entry point in closer to your battery box.  I'm sure you have thought considerably about this as you want to minimize your cable length and access the battery to eliminate any voltage drop or loss via distance.  I'd have to look at this closer but am betting others have posted write-ups on the net regarding suggested cable lengths and in an effort to maximize charging from the panels.  

Are you using the Renogy flexible panels?  I love the looks of those things and know that there are some T@B units out there with them secured to the roof line.  Two 100 watt panels would make a huge difference and allow charging during travel or just sitting idle at home, in the camp ground, etc.  I also like the looks of a solar charge controller inside the trailer or even in the galley area.  



Make sure that you document your work, take plenty of photos and post them to the forum as this is what the forum is all about and your innovations will help people down the road and out in the future.  I love solar and have a 100 watt Renogy panel mounted on the side of my garage that I use to charge up my trailer battery when it sits idle.  Good stuff and post up your work as things progress!

Lisa33

This won't help you since you have a Clamshell with no plastic trim.  However, I thought I'd share that on my T@DA, I used the plastic trim as a channel for the wires. This might be helpful to others with non-clamshells.  If you join the wires up high where it isn't visible from the ground and run them directly sideways to the trim, you can run the wires forward  inside the trim all the way to the bottom.  Then you can go under the trailer from there.  I mounted my solar controller under the lid of the LP cover and then had a very short run to the batteries.

Michigan_Mike

Were there any limitations or recommendations on the length of your lead wires from the panels to the battery or solar controller Lisa?  

Lisa33

The general recommendation is to keep the wire runs as short as possible to minimize the voltage drop.  That was a big factor in my plan.