What next? Planning my next move…..

[RandR]

I bought an RV with the start to Solar, and not knowing much about it, and a dealer that knows nothing. I probably made some less than ideal moves. So what I currently have is:
Xantrex freedom X 2000 inverter
WFCO 9855 AC converter
Zamp 30A PWM SCC
Zamp 170w PV, VOC 24.61, VMP 19.66, ISC 9.73, IMP 9.19
I have added/changed:
(2) Newpowa 180w PV‘s, VOC 19.84, VMP 16.77, ISC 11.75, IMP 11.20
(2) 200AH Lifepo4 batteries
Victron smart shunt
Batteries and solar are all wired in parallel
I suspect this may not be optimal as I can see my charging volts are never over about 13.8V, and charging amps run around 15. Not much higher.
Right now I have a 12V 10 cuft refrigerator, that draws about 4.5/5.0 amps and it keeps up as long as the sun is out. Just east of Tacoma WA.
Thanks in advance. Bob.

 

[RandR]

I know someone must have some input on this. I have tried a few vendors for input, which is how I got here. What I think I would like to try is a Victron MPPT, just because it might give me some more information. I would really appreciate any help.

 

[NwCali]

Seems your panels are either not enough or not putting out enough to me. I'm still newish to this though.

 

[RandR]

I think I have about 530W of solar, if my math is right that should be 31.6A, at 16.77V? Part of why I am having a hard time with selecting an MPPT. Also have heard I shouldn’t do any series wiring with 3 PV’s, but not sure of that either.

 

[NwCali]

You seem to have a LOT of battery though and you say you barely keep up with the load during the day. From what I gather its best to overpanel. "winter is coming" as well and this will impact your input via solar, but again you have a large battery.

Hopefully someone else will chime in.

 

[RandR]

I want to add more PV as well, just feeling like I would like some advice as to what to do next. Thanks!

 

[RandR]

I have to say I am surprised. I have read probably hundreds of posts on here, learned a lot. So I thought I would try to articulate an issue I cannot figure out. With all the knowledge on this forum, this is all the feedback I can get? Help please!

 

[12VoltInstalls]

Your 170A panel and the other two aren’t well matched. Leave the zampa on the pwm and get a mppt for the other two. (If you ever want to you can add two more 180W panels 2S2P and have more sun time power)

Are the pwm parameters programmable?
What are your batt specs?

 

[RandR]

The Zamp 30A SCC is not programmable to the best of my knowledge. Other than battery type selection. Is there any series/parallel wiring I can do with these 3 panels, that might improve the situation?
I have (2) 12V 200AH Lifepo4 batteries.

 

[12VoltInstalls]

With the current equipment and panels? No.

You need four or six or 8,9,10,12 etc panels to make anything work other than 3S or 3P

 

[Wellbuilt]

At noon with the Panels facing the sun you could get 31amps in a perfect world , but your panels will only put out 75% of there rated power and then if they are laying flat
You lose more out put then the panels are miss matched .
I would get a good mppt controller and wire your 2 180 watt panels in series .
Then aim them at the sun and see what you get .
2 more panel will help your cause
I think you just aren’t getting enough power in .

 

[RandR]

Thank you both for the reply’s! It sounds like my choice of PV’s is worse than I thought. I am stuck with the Zamp panel, but the Newpowa‘s can be changed easily. Is there a combination that might work better? I have 10’ of unistrut, (used by the newpowa panels)and hope to add that much more in the future. I ordered a Victron 150/60 MPPT, to see what change it would make, and to give me more information. Thanks again, any more thoughts are appreciated!

 

[MisterSandals]

Your 3 panels in series should produce:
19.66V + 16.77V + 16.77V = 53.2V
But will be limited to 9.19A
53.2V x 9.19A = 488.9W

I think your Zamp may be limited to 50V max input?

With Victron MPPT
489W / 12.8V = 38A charging

3 panels in parallel:
9.19A + 11.2A + 11.2A = 31.59A. (This will exceed most y connector ratings)
This will be limited to 16.77V
31.59A x 16.77V = 529.7W. (Better than series)

 

[RandR]

Ok so right now they are wired in parallel, I have exceeded the Y connector rating? I looked at Zamp’s information I do not see a max voltage. I read in someone’s post that with a PWM SCC, that it would limit charge to battery voltage? That seems true as since I installed my battery’s, new solar panels, and Victron shunt. I seldom see more than 13.8 volts.
Anyway 1: what can I do to with my Y connector. I have 1, plus the roof Gland? This sounds like it needs to be fixed! Thank you!

I realized right after I posted I have 2 Y connector’s, 1 positive and 1 negative!

 

[MisterSandals]

I have exceeded the Y connector rating?

Most that I have seen are 30A max.

I seldom see more than 13.8 volts.

Are you sure your SCC is set for LiFePO4?

I realized right after I posted I have 2 Y connector’s, 1 positive and 1 negative!

is that a 3:1 Y or how are you connecting 3 panels with 3 fuses in parallel? Happen to have a pic?

 

[RandR]

I am sure you are correct about the Y connectors, they are just whatever off Amazon. My mistake.
Yes my Zamp SCC is set for LifePo4 Batteries.
Sorry no pictures of that at the moment, basically I used the Y’s to connect the Newpowa panels, then to the SAE dual roof port with the Zamp panel in the 2nd one.
As I learn, I am correcting the problems of the RV manufacturer, today I am installing a 2 pole solar disconnect. There are no fuses in the PV wiring.

 

[RandR]

Here is today’s work, we will see what tomorrow brings!