Wiring Panels

[J & J Bumblebee]

I have a Victron 100/50 MPPT. I'm installing four 200w 24v panels using 10 awg wires. It's all going on top of a 2021 22 RBE. Should I go series or parallel? I'm guessing I could do either. Thanks!

[StephenO]

Your Victron 100/50 controller can only accept an input PV (photovoltaic voltage I believe) of 100v, and 4 of those panels in series will exceed that I'm pretty sure. You'll likely want to do a combination of series / parallel, so two panels in series and two of those series combinations in parallel.

You can also use the Victron MPPT calculator to help with your system planning

https://www.victronenergy.com/mppt-calculator

[J & J Bumblebee]

Your Victron 100/50 controller can only accept an input PV (photovoltaic voltage I believe) of 100v, and 4 of those panels in series will exceed that I'm pretty sure. You'll likely want to do a combination of series / parallel, so two panels in series and two of those series combinations in parallel.

You can also use the Victron MPPT calculator to help with your system planning

https://www.victronenergy.com/mppt-calculator

Thank you!

[J & J Bumblebee]

This is what I came up with...

[howson]

J & J Bumblebee

That configuration looks good to me.

The two panels in series have a combined maximum open circuit voltage (VoC) of 45.4x2=90.8vDC. Nearly a perfect match with your Victron 100/50. (For those who don't know, the first number is the maximum voltage that can be applied to the input of the solar controller.)

Now with those two series-pairs in parallel: For output, the maximum under ideal test conditions is 800W. Using 14.2vDC as the assumed output of the controller to the battery bank (could vary based on battery state of charge) and the maximum amperage output of the controller (the second number in the solar controller) which is 50A, that's 14.2v x 50A = 710W.

Initially that output may look like a mismatch since the panels are theoretically capable of generating additional power, but I wouldn't worry about the fact that the panels could output 800W yet the maximum you're going to get out of the controller is 710W. It is very rare to get the maximum output from an array. I've seen (once) 1100W from my 1200W setup.

The graph below is from Victron's VRM website and is an estimate on the solar irradiance my array will experience today and tomorrow. It clearly shows the variance from sunrise to sunset. Also consider the angle of the sun to the array is constantly changing (rarely ideal) and hopefully the previous paragraph makes sense.



Hope that wasn't too much info.

[J & J Bumblebee]

Thanks, Howard!

It wasn't too much info for me, and it's nice to have confirmation.


John