Wiring for hatch mounted solar panels (26M)

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Balmain Bug
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Wiring for hatch mounted solar panels (26M)

Post by Balmain Bug »

Hi Guys,

I'm thinking of mounting a couple of solar panels on the hatch cover and wondered if anyone else has solved the problem of flexible wiring. Obviously there would need to be some sort of wiring loop between the hatch and the inside so that the hatch moves freely.

These are a couple of fairly cheap 20W panels to trickle-charge the batteries and run a small fridge.

TIA

Steve
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March
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Re: Wiring for hatch mounted solar panels (26M)

Post by March »

Hi, Steve:
I assume that these are the 20W flexible panels? 40W would not be enough to trickle-charge your batteries if you plan on using an electric cooler. Even the Danfoss compressor (reputedly the best in the business) will require more than that. I used to have a rigid 64W permanently mounted in the back and ( with a Waeco 50L fridge) it was sufficient, but only on a sunny day. I added a second one and now everything's good. However, I was thinking of adding a flexible panel and facing the same hurdle--\

My Mac already has a cigarette lighter plug on port side companionway. I was planning to use that, quick and dirty. My second option that was more elaborate was, install a second plug by the mast, but that would have meant running electric lines inside, between the lining, etc etc. As you probably realized, the cable will be in the way, especially if you make it long enough to allow the hatch to slide forward and backward

I finally went with a second pannel that I added permanently in the back
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Chinook
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Re: Wiring for hatch mounted solar panels (26M)

Post by Chinook »

I installed my 65 watt solar panel on the sliding hatch. I bolt the angle brackets it came with to the sliding hatch with 4 bolts. I use wing nuts and rubber washers, to prevent leaks around the drilled bolt holes, and to make it easy to install and remove. I have a 26X, and was able to run the wire up from the battery box and into the stainless steel support pole which mounts on the aft end of the galley and attaches to the cabin roof near the sliding hatch track. I drilled a hole in the stainless pole so the wire could exit near the top of the pole. Next, I drilled a hole into the fiberglass sliding hatch track, which is hollow, and ran the wire down the track a short distance, and drilled another hole at a point midway along the sliding hatch when it's in the closed position. With the wire fished out of the hole there and up through a hole drilled in the hatch cover (sealed with 5200) I left enough exposed slack wire to allow the hatch to slide all the way open. When it slides closed I have a short loop of wire, high above the galley (perhaps 6 or 7 inches long). I considered attaching some sore of bungee or rubber band to the wire, to keep it up near the cabin roof, but it hasn't proven to be in the way. As I recall, the 26M doesn't have a support pole, so this route wouldn't work, but perhaps the wire could be fished up to the hatch track by another means.
Balmain Bug
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Re: Wiring for hatch mounted solar panels (26M)

Post by Balmain Bug »

Thanks for the replies. I should have said I need to run a small 12volt 45 litre cool box (not a fridge) just to keep our drinks cold. The 40 watts (2 x 20w) solar panel is just for this purpose as my current battery set up is fine (before I got the cool box). I am thinking that the sliding hatch lid is a good out of the way place to fix them but just need some advice on the wiring. Cheers.
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kmclemore
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Re: Wiring for hatch mounted solar panels (26M)

Post by kmclemore »

I have a 40W Kyocera on my hatch cover. To wire it I used the reclaimed coiled cord from a hair dryer... it was the perfect thing. I routed a wire from the panel, through a small hole in the hatch and connected it to the coiled cord at the front edge of the hatch cover. The other end of the coiled wire connects to the leading edge of the hatch opening, and then along the starboard side, across the top-edge of the front of the head enclosure, then down the side of the boat and under the dinette. With the hatch open, the coiled cord stretches forward to allow the movement, but when you pull it closed the coils re-compress and keep the cord nice and tidy.
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Nick
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Re: Wiring for hatch mounted solar panels (26M)

Post by Nick »

If the wires exit the track exactly half way down and enter the hatch at the back then the wires can be fairly taut in both the fully closed and fully open positions which is what it is in most of the time. Cheers Nick
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Sumner
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Re: Wiring for hatch mounted solar panels (26M)

Post by Sumner »

Balmain Bug wrote:............ I need to run a small 12volt 45 litre cool box (not a fridge) just to keep our drinks cold. The 40 watts (2 x 20w) solar panel is just for this purpose ...........
How many amps does that 'cooler' use? Most of the ones I've seen use over 4 amps and usually use more than the 'frigs' that have been mentioned that have a compressor. The frigs cycle on and off, but I think the cooler will run continous. I have one in my teardrop trailer and it can run an RV battery flat in about 8 hours.

Your 40 watt combined panels are going to put out around 3 1/3 amps at their best for a few hours a day. If you are just trying to slow the discharge on your batter the panels will help, but I seriously doubt they will supply the electricity needed by the cooler.

Good luck and I like the coiled cable idea that was mentioned myself.

c ya,

Sum

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Balmain Bug
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Re: Wiring for hatch mounted solar panels (26M)

Post by Balmain Bug »

Hi Guys,

Thanks for all the tips here - there's a lot of good stuff.

I will be starting this job in a few weeks and I'll post how I finally fitted them.

Cheers

Steve
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