System spec'ed with mismatch panels

[Florida Flyer]

Do you mean run the two smaller panels in series, then parallel that with the bigger panel ? I dont think you should series them all, as the two lower voltage panels would drag down the higher one. What have you done, how's it working ?

[NickinCO]

Will do. New plan is to run them all in series. Test run the end of this month to see what I really need and I'll be building it out next week.

[bcroe]

I predict that your proposed arrangement will work well. Bruce Roe

[Mike 134]

Never tried that combination let us know how it works

[azdave]

Lol. Thanks?

At least you got a reply.

I'd be glad to help if I could but I'm strictly a simple grid-tie system owner and the only batteries I charge are inside my mobile phone.

[NickinCO]

Google is your friend.

Lol. Thanks?

[J.P.M.]

No replies... wow. Alright. For anyone else interested I'm planning on running all 3 panels in series. If anyone knows of a more active message forum on this topic please let me know.

Google is your friend.

[NickinCO]

No replies... wow. Alright. For anyone else interested I'm planning on running all 3 panels in series. If anyone knows of a more active message forum on this topic please let me know.

[NickinCO]

Howdy,

First time poster here. This is not my first foray into 12v solar but it's the first time using mismatched panels.

My RV came with a 300w Jamboni panel that retails for $750. In an effort to use that panel but double my wattage this is the most cost effective method I’ve come up with, can you confirm it will work? I’m also open to other ideas but this method would allow me to not remove the stock panel and also utilize stock wiring. I also don't understand what effect differing open circuit and short circuit current may have on the system.

The factory Jamboni 300w panel specs are as follows
300w
32.26v
9.3a
open circuit v 39.85
short circuit current 9.75

I’ve found “NewPowa” panels that have a pretty similar spec that are much cheaper - $175 each

160w
16.7v
9.3a
open circuit voltage 19.83
short circuit current 9.75

If I run two NewPowa 160w panels in series that would create
33.4v
9.3a

Then I could run those two that are in series, in parallel with the 300w Jamboni and my specs would be

32.26v
18.6a
= 600 watts, so I'm shorting myself 20 watts with the mismatched voltage but for the cost savings it's worth it. In the future I could continue to add strings of 160w panels in series (with larger wiring) if I needed a more robust system.

I want to replace the stock charge controller with a victron model as well. Their calculator is a little confusing, from the best I can tell they are recommending a 150/45 model for this system? Does it make sense to upsize a little?

This system will be used to replenish two SOK 206ah lithium batteries connected in parallel.

Thanks
Nick