Should I switch from series to parallel?

[jfrasier71]

So a couple months ago, I installed my first system in my RV (with great help from the community btw)

OK need a little help with my first system

Ok been following solar and your videos, but I think I may have borked it. I am moving into my RV for a while, and I work on my computer alot. So I wanted to set up an independent system just to run my desktop computer, my cellular modem and my monitor (maybe a couple led lights hence the 12v...

diysolarforum.com

Currently, I have a series connection, and am only outputting around 80v and 1.6a on a good day from 2 200w panels. I suspect that is because I am in series, and it is causing a loss due to one of the panels being shaded. I am planning on switching to parallel so that each panel will work on its own. But that will lead to more heat in my wiring. ATM, I am using 12g solar panel wiring, around 13 ft of it. I looked at the chart, and it looked like it would be ok, but should I change that to a thicker gauge to compensate for the heat, maybe 10g or should I be ok with the 12g?

 

[timselectric]

Your solar panels should have bypass diodes in them, to compensate for shading. Unless they are low quality, portable, or very old.

 

[Will Prowse]

Those pv conductors can easily handle that current with very little loss. Should be fine. I would check every connection first. Especially the mc4 connections.

Years back I found a really nasty bad connection in my own pv junction box on the roof of my rv. It was causing all sorts of problems I couldn't seem to figure out.

 

[timselectric]

Series equals higher voltage, which means less voltage drop. I'm not sure what advantage will be gained by switching to parallel. But, please let us know.

 

[Will Prowse]

Parallel can be advantageous if using a PWM controller. That's about it.

In my beginner book I recommend parallel series connection to avoid higher voltages. Trying to make it as safe as possible for beginners. They will have to work with PV controller input terminals and I would feel awful if something bad happened.

But for everything else, always implement a series connection. The higher the voltage the better.

 

[jfrasier71]

Parallel can be advantageous if using a PWM controller. That's about it.

In my beginner book I recommend parallel series connection to avoid higher voltages. Trying to make it as safe as possible for beginners. They will have to work with PV controller input terminals and I would feel awful if something bad happened.

But for everything else, always implement a series connection. The higher the voltage the better.

No I have a MPPT controller. I remember reading in the book that in a series connection, both panels work as one and if one is in the shade it could negatively affect the voltage output. I just checked all my connectors, and they are tight. Could it be a setting in the MPPT that is keeping the voltage so low? They are not cheap or old panels either. I purchased 2

RICH SOLAR 200 Watt 24 Volt Monocrystalline Solar Panel High Efficiency Solar Module for RV Trailer Camper Marine Off Grid​

Amazon.com

When I went up on the roof to washed them off, I noticed there was a little flex bending in the panels not sure if that could cause any issues or not.

 

[timselectric]

No I have a MPPT controller. I remember reading in the book that in a series connection, both panels work as one and if one is in the shade it could negatively affect the voltage output. I just checked all my connectors, and they are tight. Could it be a setting in the MPPT that is keeping the voltage so low? They are not cheap or old panels either. I purchased 2

RICH SOLAR 200 Watt 24 Volt Monocrystalline Solar Panel High Efficiency Solar Module for RV Trailer Camper Marine Off Grid​

Amazon.com

When I went up on the roof to washed them off, I noticed there was a little flex bending in the panels not sure if that could cause any issues or not.

Those are equipped with bypass diodes.

 

[jfrasier71]

So I found the problem, the controller was set to 12v rather than 24v.

 

[Seaninnj]

Parallel can be advantageous if using a PWM controller. That's about it.

In my beginner book I recommend parallel series connection to avoid higher voltages. Trying to make it as safe as possible for beginners. They will have to work with PV controller input terminals and I would feel awful if something bad happened.

But for everything else, always implement a series connection. The higher the voltage the better.

I love it when you make my life easier.

I'm doing my first solar install on our travel trailer, 2 200W Rich Solar panels going into a Victron 100/30. The rest of the system is Victron mostly I tackled everything else and now it's time for the final components, the panels and solar charge controller. I've been going back and forth on serial vs. parallel as I can do either but I will start with serial based on your proclamation.

Thanks for all you do !