How to physically wire several solar panels into one MMPT controller?

[webcraft]

I have a Renogy Rover 40 MMPT controller. It had 2x65W panels wired to it. One panel has died.

I want to add another 2 100W panels, plus the remaing 65W panel, and also have a flylead I can use occasionally with a 100W folding panel with Andersen connectors, so max possible would be 360W of panels but normally 260W

I plan to use this connector and 5m 4mm2 wires (approx) to the controller.

It all seems well within spec, but I thought I would run it past the panel first in case I am missing something.

 

[PaulRainbow]

You should not mix panels of different wattages and voltages. The 65W panel is likely a different voltage, as well as wattage. I would leave the 65W panel on the Renogy controller and fit a second controller for the 100W panels. If the folding panel is the same voltage to could use that with the fixed pair.

Someone will come along shortly and tell you that you need 4 controllers, one for each panel.

 

[Sea Change]

Someone will come along shortly and tell you that you need 4 controllers, one for each panel.

It can be the best approach, but unlikely to be cost effective with panels at this size.

 

[webcraft]

You should not mix panels of different wattages and voltages. The 65W panel is likely a different voltage, as well as wattage. I would leave the 65W panel on the Renogy controller and fit a second controller for the 100W panels. If the folding panel is the same voltage to could use that with the fixed pair.

Someone will come along shortly and tell you that you need 4 controllers, one for each panel.

The 100W folding panel says 17-22 volts

The rigid 100W panels spec is attached

 

[webcraft]

And the 55W panel is 17 volts as well, so they should all be OK?

 

[PaulRainbow]

And the 55W panel is 17 volts as well, so they should all be OK?

I'd keep the 65W one on its own controller. The other 3 should be OK sharing a controller.

 

[noelex]

For parallel connection, as a rule of thumb, the Vmp of the different panels should be within 0.5V for reasonable performance.

The specifications you have are ambiguous, but they suggest the Vmp of the 65w panel is 17V, the 100W panels have a Vmp of 17.1V, and the 100w folding panel likely has a Vmp of 17V.

Ideally, the Vmp is converted to real-world values, making allowance for the temperature, but this requires the temperature coefficients of the various panels, which is not listed. Your various panels have quite a close voltage match, well within the 0.5V limit, and it is very unlikely that allowance for the various temperature coefficients would put you outside the range.

Connecting all the panels in parallel to your Renolgy controller will work satisfactorily. Using more than one controller would give you better performance, especially if the panels are subject to different lighting conditions, which seems likely, but this is not essential and the performance increase would likely be modest.

The only extra consideration is: If you have 3 or more strings in parallel (as you will have), each string needs one fuse. So you should install a fuse on the output from each solar panel. Fused MC4 connectors are often the easiest way to incorporate this.