adding panels

[townline]

Looking for advice on wiring 3 100watt panels.
 Currently have 2 panels wired series.
Plan  on using rover 30mppt.

 

[user 423]

The Renogy site has good info you could check out.

Pros and cons of series vs. parallel,etc.

 

[jimindenver]

As long as you remain within the controller limits on Voc you are good. I would normally only suggest running 2 panels in series but you can’t do that with 5 panels so either run them all together in series or all in parallel.

 

[gizmotron]

I'd like to know if I could run the same 100 watt Renogy panels in both parallel and series with or without a joiner box of some kind. I've seen a video where the person demonstrates using a combiner box of some kind. I would like to run panels 1 & 2 in parallel with 3 & 4 also in parallel and have those two groupings run in series. If that is possible then I could add two more parallel panels and still be under max voltage and max amperage.

 

[tx2sturgis]

Looking for advice on wiring 3 100watt panels.
 Currently have 2 panels wired series.
Plan  on using rover 30mppt.

Lots of workable solutions...what *I* would do is leave the two series panels as-is, feeding a controller and the house battery.

Then add the 3 panels in series on a separate controller, feeding either the same batteries or a separate bank of house batteries.

Redundancy is a good thing. You have a back-up in case of failure of one or the other.  One system can run a fridge and maybe a few LED lights, the other system can run your phone charger and laptop etc.

Depends on the room you have to work with, and your energy needs.

 

[gizmotron]

I would like to run panels 1 & 2 in parallel  with 3 & 4 also in parallel and have those two groupings run in series. 

I found something that might help me on this. I should run 1&2 in series, the same for 3&4. Then combine these higher voltage outputs in parallel on the way to the controller. Higher voltage and lower amps is better on the wires. Still want to know if a combiner box is recommended. I'll have to watch that whole video again. That guy is a total expert on this stuff.

 

[gizmotron]

OK, I found what I need. I'll be using MC4 combiners and inline fuses.



Found it regarding fuses:

 

[Tom_M]

It's unclear whether the OP will have a total of 3 panels or 5. A typical 100 watt panel will have a Voc of about 20 volts and 5 in series would be 100 volts. As mentioned, make sure your controller can handle this high of voltage.

 

[Freelander]

I have 4 100 watt panels in parallel and can get 20 volts and I have seen up to 300 watts for about 20 amps.

 

[wayne49]

No "combiner box" is needed, just a bunch of pairs of "two into one" MC4 'Y' connectors. Some for the negative joins and some for the positive joins.

https://www.amazon.com/s?k=B07HGMN7D9

Get some colored electrical tape to mark the cables and panels, to track which cables go to which panel and to which set of panels.

I do two sets of two panels (40V @ 5A) serially, then in parallel to the controller for 40V @ 10A.

 

[wayne49]

80 volts is too high as it wastes energy by creating heat, reportedly stated by a Renogy spokesperson at an RTR long ago.

The post is somewhere back in time on this forum.

 

[abnorm]

The ROVER is a 100 volt 30 amp MPPT controller

 

[gizmotron]

No "combiner box" is needed, just a bunch of pairs of "two into one" MC4 'Y' connectors. 

Yep, thanks. I saw that in the videos that I watched. Nice. I've got enough room and component capacity for two more 100 watt panels if I go series/parallel. All I have to do is bash my head on the ceiling when using the toilette. So I can mount 6 on top. Going to do some testing. Head bashing testing that is. I don't need a top mounted exhaust fan because I'm installing a ductwork system that exits down in one instance and secondarily out the side in the other with four computer fans to run it. It's a staged exhaust system designed to let out condensation in cold months. I like the idea of two more 100 watt tilt-able panels. I also like the idea of a pop up, full stand up, shower where I don't bump my head when the popup is in the down position. I've got all winter to decide.

 

[Tom_M]

The Rover 30 has a maximum input of 100 VDC. 5 panels in series would be 100 VDC. There most likely would be times where the voltage would go higher than 100 VDC so there would be a chance of frying the controller.

 

[townline]

Looking for advice on wiring 3 100watt panels.
 Currently have 2 panels wired series.
Plan  on using rover 30mppt.

 

[townline]

I have decided to add a single panel with controller and have 2 systems in the van.
 The renogy kit has a 30 mpt which will be adequate for the single panel or could
 handle all 3 in paralell if needed for a backup controller.  I also have two 18amp agms
 that are not being used right now. It seemed easier to leave existing setup in place as
the new panel is only 40' long which fits into the rack a lot better.  If had planned better
 would have made rack brackets with more space the between them as i had to cut the
 base of the Z brackets to make the panels fit.