400W Solar installed on 5th wheel, ready to upgrade

[corn18]

I finally got the 2x200W Rich solar panels installed on strut channel. All hooked up and working. I have another 2x200W Rich solar panels with 40A MPPT on the way. That will give me 800W and 2xMPPTx100V/40A. I decided to run 2 sets of 10ga wire from the roof, so each SCC will have its own wires to the roof.

I think I want to over panel both SCCs by adding a third panel to each circuit in series. So 3S x 2. Not really 3S/2P because I will be bringing down each 3S on the dedicated 10ga wires. That will give me 1200W of solar but I can only use about 1000W max due to the SCCs. I'm ok with that. I like the idea of over panelling because I will never tilt the panels.

My question is where should I put the third panel for each circuit? I can fit 12 panels on my roof. I am thinking adding them forward of the 4 I will have on the roof already. Appreciate your thoughts. Always helpful to get another set of eyes and idears.

[rk06382]

Originally Posted by corn18

I finally got the 2x200W Rich solar panels installed on strut channel. All hooked up and working. I have another 2x200W Rich solar panels with 40A MPPT on the way. That will give me 800W and 2xMPPTx100V/40A. I decided to run 2 sets of 10ga wire from the roof, so each SCC will have its own wires to the roof.

I think I want to over panel both SCCs by adding a third panel to each circuit in series. So 3S x 2. Not really 3S/2P because I will be bringing down each 3S on the dedicated 10ga wires. That will give me 1200W of solar but I can only use about 1000W max due to the SCCs. I'm ok with that. I like the idea of over panelling because I will never tilt the panels.

My question is where should I put the third panel for each circuit? I can fit 12 panels on my roof. I am thinking adding them forward of the 4 I will have on the roof already. Appreciate your thoughts. Always helpful to get another set of eyes and idears.

I over paneled my Victron 50a MPPT. I have two pairs of 10 awg cables feeding the MPPT from ten 100w panels. Max output is 50a x 14.6v or 730w. I have seen 650w in direct sunlight.

Ten 100w panels on my roof:


Two pairs of 10 awg cables joined to 8 awg going the MPPT.


In June-July I see about 4kw a day. By Sept, it drops to 3kw a day. This winter I am going to add a tilt by installing longer Z-brackets on one side of each panel. Five tilted left & five tilted right for the lower sun in Alaska.


Back to your setup: A 10 awg cable is should be limited to 30a or you will get line loss. You should use two pair for each 40a SSC. I would put three panels on each side.

Keep us updated.

[corn18]

Originally Posted by rk06382

I over paneled my Victron 50a MPPT. I have two pairs of 10 awg cables feeding the MPPT from ten 100w panels. Max output is 50a x 14.6v or 730w. I have seen 650w in direct sunlight.

Ten 100w panels on my roof:


Two pairs of 10 awg cables joined to 8 awg going the MPPT.


In June-July I see about 4kw a day. By Sept, it drops to 3kw a day. This winter I am going to add a tilt by installing longer Z-brackets on one side of each panel. Five tilted left & five tilted right for the lower sun in Alaska.


Back to your setup: A 10 awg cable is should be limited to 30a or you will get line loss. You should use two pair for each 40a SSC. I would put three panels on each side.

Keep us updated.

Nice setup! I may end up with 10x200W at some point, but 6x200W will work for now.

Since I am running 2S right now, that is 41V @ 9.8A. The 10ga wire is more than enough for that. When I go 3S it will be 62V @ 9.8A, so still good to go. I could go as high as 4S/2P on the 10ga wire (84V @ 9.8A) and still be fine. Will need a few more SCCs if I go with 2000W of solar.

[harrydodge]

Iam thinking about panels on my Columbus 320rs. Are you just putting screws in the roof , If not how are you finding the truss's. Palamino will not give you any info besides there are few truss's and lauon plywood over Styrofoam insulation for the roof construction? Your solar looks great ,as soon as I feel comfortable with securing them to the roof? I will be doing the same.Thank you Harrydodge

[corn18]

Originally Posted by harrydodge

Iam thinking about panels on my Columbus 320rs. Are you just putting screws in the roof , If not how are you finding the truss's. Palamino will not give you any info besides there are few truss's and lauon plywood over Styrofoam insulation for the roof construction? Your solar looks great ,as soon as I feel comfortable with securing them to the roof? I will be doing the same.Thank you Harrydodge

I felt the same way as you with the same questions. I had the panels assembled and ready for install for several weeks. I was not sure enough where the studs were or if the underlayment itself would hold up. I couldn't find the crossmembers with a stud finder, either.

Then I posted a pic of my roof on here and a nice poster pointed out you could see my crossmembers in the pic. They looked like seams but weren't. So I hoisted the panel assembly up on the roof and got brave enough to start screwing lag bolts into the "seams". Sure enough, there were studs underneath. I did miss one crossmember with a lag bolt and it just kept spinning, so whatever the underlayment is, it is not strong enough to hold the panels.

I will say using strut channel is a great method. Very secure and allows me some flexibility on how I mount the panels to the strut panel.

Next set is assembled and ready to go up on the roof. I'll be up there as soon as it stops raining.