Adding more solar tech question different Wattage

[calisparky]

On my 2018 Jayco North Point 377RLBH I have an opportunity to add a couple more solar panels from left overs from a buddy of mine to add to my existing system. WILL THESE WORK WITH MY EXISTING SET UP......



Existing on my rig-
8 X 100W on the roof. 400Ah lithium.


CHARGER-Nomenclature specs-

Renogy Rover Charger. 40A MPPT Charge Controller
RNG-CTRL-RVR-40
Charge A-40 Load A 20
MaxV Power PV 550W(25c)-1100W(-25c)
(30001) 202816220119..... (assuming serial number info)


CHARGER ON SCREEN DISPLAY-

14.0 (middle of screen) Showing 12V at lower left
SCROLL UP showing (first click up arrow....)
Shows solar symbol- 68.5V to 70.3V varies, assuming incoming solar voltage
21.09A
100%
SHOWS BATTERY SYMBOL-
14V
SHOWING BATT and SOLAR SYMBOL
17Ah


That's what I could find on the charger. The inverter-
Xantrex FreedomX 1200.


400Ah Lithium 1 yo batteries. 4X100Ah. I will be adding when finances are a bit more agreeable as these don't tend to make it through the night, especially winter nights.



THE PANELS I COULD ADD INFO- On sticker/nomenclature...
Model SSG250P-60 250Wmax
Open circ V-37.6
V @ PMX-30.3
Short circ A-8.85
A @ PMax-8.27
Max system V-600
Fuse Rating-15A



These panels have different style connections on both the wires on them so I'd have to update them to the type on the trailer. Is that a big deal? There appears to be a J-box where the wires go to the back of each of the panels.

I'm still "up in the air" about placement of an additional 2 panels. I've got room on the roof but likely plug into the wet bay plug for the time being to direct them, then maybe on the roof later.



This trailer MUST HAVE HAD panels on it when new for the Residential fridge I'm assuming though doesn't specify that on the original sales slip/contract.



I am retired specialist Electrician for motor control/troubleshooting and about everything else to do with AC electricity. Just not a damn thing about solar. By the time I became contractor, the solar field/sales had already blown up with everyone and their sister selling/installing it. I was already too busy to deal with the door to door BS anyway!

If anyone has better knowledge than this idiot and can point me in the right direction, and are the 250W compatible with my existing, I'd greatly appreciate any info you've got.

 

[colby-JAY]

You will want to run a separate line down to a second charge controller to get the full efficiency of all of the panels. Have a look at this video from Explorist.life to see what the effects of using panels that aren't matched together - https://youtu.be/jejro4zkl8I?si=I1UNdxI8QkVHOp4u

 

[MrKABC]

You will want to run a separate line down to a second charge controller to get the full efficiency of all of the panels. Have a look at this video from Explorist.life to see what the effects of using panels that aren't matched together - https://youtu.be/jejro4zkl8I?si=I1UNdxI8QkVHOp4u

Agreed, I learned the hard way that mismatched panels don't work. (at least not very well).

Now I am going to throw away my old non-matching panels and get the newer, better "bifacial" ones for all.

 

[calisparky]

Thank you for this info.
I do appreciate it.

 

[RogerR]

Not an engineer but my questions would be are the roof to MPPT wires big enough?? Adding a second run vs. buying new panels a better idea than a second run?

Is the 40 amp MPPT big enough to handle the extra from 2 more panels?
Since you have Renogy, how about a call to one of them for any of these questions? I found them helpful when I put in my Renogy/solar/lithium setup.

 

[calisparky]

Not an engineer but my questions would be are the roof to MPPT wires big enough?? Adding a second run vs. buying new panels a better idea than a second run?

Is the 40 amp MPPT big enough to handle the extra from 2 more panels?
Since you have Renogy, how about a call to one of them for any of these questions? I found them helpful when I put in my Renogy/solar/lithium setup.

Yeah, that would certainly get me all the correct answers for this idea, just thought I'd hit up on this page to share what I might learn for others one day as well.

What you mentioned is a good point though. I don't know enough about solar systems, even as a career electrician that never got involved in the hype of it all. It's a (sing with me....)Whole new world with solar!! lol