Friday, February 22, 2019

Day 45 - More Solar

This morning at around 7:30, I started the installation of the new solar panel. It was about 45°F but there was no wind. I didn't want to be messing around with a huge sail up on the roof of the RV. I marked the area on the roof where the mounting brackets would go and covered the area with a piece of Eternabond tape. This is a very sticky sturdy tape that is designed to repair rubber roofs. Once it's on, it's on for good. This helps seal the screw holes in the roof. The rear brackets landed on a roof truss which is always nice. The vendor had 3M tape on the "L" brackets which was nice to hold the bracket in place while the pilot holes were drilled and the stainless steel screws driven in place.

In this picture, you can see the size difference between the 100-watt Renogy panels and the new 180-watt panel. Almost double the size. At this point, the panel is screwed down to the roof and I'm headed down to get some coffee and let things warm up some. The next step is going to be to seal things up.

I'm using Dicor self-leveling sealant which is designed for membrane roofs. I applied the Dicor over the screw heads, around the base of the bracket, and around the edges of the Eternabond tape. Around the tape edges probably isn't necessary but I needed to use up the tube once it has been opened. I also went ahead and applied some over the screw heads of the other solar panel brackets and anywhere else that looked like it needed it.

I used the tilting brackets to get access to the junction box where the 10 AWG wires from the panels are screwed into bus bars along with the 4 AWG cables that head down into the basement storage area. The 4 AWG cables are 12' long and are sized to handle the 45 amps that the controller is rated at. I was originally going to rearrange the cabling of the other panels but decided to just drill into the box, run the new cables and seal up around the cables with Dicor. I figured that the box is now in a pretty protected location being under the solar panel.

Can you tell when I plugged in the new panel? The charge current jumped from about 16 amps to 25 amps. This was with the panel tilted towards the sun. After I got done with the cabling, I moved the panel back to the flat position. These brackets don't seem to be as sturdy as the non-tilting Renogy brackets. Adding the tilting ability does seem to make the brackets a little more flexible. The brackets are now in the upper of two positions which would put slightly more stress on the "L" brackets and the roof screws. Tomorrow, after the Dicor sets up, I'll see if I can move them to the lower position and still have a little space between the junction box and the panel.

Anyway, this was a good upgrade and the installation took a couple of hours. If this panel continues to work out, I may pick up one more. Right now, I have 580 watts of panels on the roof. 

8 comments:

  1. Replies
    1. I really enjoy projects like this. It was pretty cut and dry as I had done the other four panels.

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  2. Nice addition! Do you think you will ever use the tilt?

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    1. I don’t know. Probably not. I picked up the tilt brackets so I could mount the panel over the junction box. It’s easier to just add more panels to compensate for lower sun angle, assuming you have the space. If you are limited then tilting may be necessary to meet your charging goal.

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  3. Fun adding more panels and seeing the change in output! Time for more boondocking.

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  4. Next stop is boondocking near Joshua Tree. I'm hoping that with all this rain the sun will come out and we'll have flowers in JT.

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  5. Replies
    1. And it seems to be working pretty good. One of the reasons for the additional panel is to be able to run the refrigerator off of the inverter while traveling.

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