Installing 2 new solar panels

[Breadman99]

Hello,
I currently have installed on my travel trailer, a Renogy Rover 40amp controller with a factory Go Power 100 watt panel. I just purchased two 100 watt Eco-worthy panels and would like to install them. I'm curious as to my options for install. Should I?

1. Install the 2 new panels in parallel and connect to the controller separately from the Go Power panel.
2. Connect all 3 panels together in parallel and run to controller.
3. Connect 2 new panels in series and run to controller separately from Go Power panel.

Any advice on these (or other) options would be greatly appreciated.
Thanks.

[creativepart]

There really is no one right way to do this. You can connect all three in parallel or in series. For 300w I’d go the parallel route, as in all 3 run in parallel to the SCC. Your SCC can handle the amps that way no problem. If there were 4-panels then maybe series/parallel would be appropriate but I can’t see doing it with 3-panels. That would needlessly complicate things.

I have 3-100w panels and run them into a combiner box in parallel with one 10-gauge wire to a 30 amp SCC.

[Breadman99]

Is there any issue running the two new panels in parallel with the existing panel? The new panels are "eco-worthy" and the existing is a "Go Power" panel.

[creativepart]

Originally Posted by Breadman99

Is there any issue running the two new panels in parallel with the existing panel? The new panels are "eco-worthy" and the existing is a "Go Power" panel.

Not generally. As long as both are the same nominal voltage, and less importantly the same wattage. They are both “12v” nominal panels with output between 18-22 volts. Correct?

Problems arise when you mix 12v panels with 24v panels, etc. And to a lesser extent when mixing 100w panels with, say 320w panels.

[Breadman99]

Correct. Same voltage for all 3 panels. Any advantages/disadvantages to running panels in series vs. parallel? I understand the advantages when running "like" panels. Just curious if the different brands of panels would make a difference.

[creativepart]

Originally Posted by Breadman99

Correct. Same voltage for all 3 panels. Any advantages/disadvantages to running panels in series vs. parallel? I understand the advantages when running "like" panels. Just curious if the different brands of panels would make a difference.

Brands shouldn’t matter at all. I mix one Zamp panel with two Renogy panels without issue. One brand is polycrystalline and the other monocrystalline, too.

There are both advantages and disadvantages to series and or parallel wiring for solar panels. Which is why I said previously that there was no one “right” choice. However, I would again not consider series wiring with an odd number of panels. Especially with such a small wattage bank of solar.

Generally you use series wiring to increase the voltage output to reduce amperage when wiring to the controller isn’t adequate gauge. There are other reasons to use series wiring, but none that really apply here.