Something wrong..

[Truck driver]

This has been really interesting. A real shit show for me to follow and decipher...

I couldn't make heads nor tails of the wiring pictures, and this:

View attachment 148975

SCREAMS the array is either in 4P or the 290W in parallel with 2S is forcing a lower voltage. The only reason I think the latter is because there was ONE day at 88V.. makes me think you disconnected your 290W panel that day. This value should be your Voc first thing in the morning before it starts drawing current. Here's my 3S array:

View attachment 148976

I'll admit your solar may be so bad that it's always trying to pull current and you're just not seeing Voc like I do.

VRM advanced tab can be really useful too:

View attachment 148977
On a 12V system there is zero reason to go higher than 36Vmp unless you need to stay under a current limitation, i.e., wiring or the 70A limit on the MPPT input.

This is further bolstered by the fact that solar appears to be absolute garbage except for the 3 afternoon hours. If there's morning sun to be had, nab it with a 5P configuration. Yes. The 290W will cause some small losses, but the MPPT conducts a sweep every 10 minutes. It's going to figure out the 4 larger panels will contribute more closer to their Vmp than the 290W panel's Vmp. Furthermore, mid-day, the front panel will have very little to offer besides Voc. The MPPT will figure out where to get the max output will be. Since the 290W Voc is higher than the 400W Vmp, there's no risk of backfeeding and the operating voltage

This should optimize your production. The only issue is you need to be able to handle 50A in the wire down through the roof.

Alternatively, get another 290W panel out of the back of the truck, wire it 2S with the other 290W and join it to the 2S2P 400W for a 2S3P array.

Interesting indeed.. but it works.. but figuring out what's causing it to not work better is frustrating.. I think it's in the 10awg wires.. BOTH pv and the wires that go to the batteries. I've tried to get anyone to come help me locally, but no success yet. So that 290w panel has been removed from the system. Yes.. it got a little morning sun but held back the others in the afternoon. So.. from here on out I want to get more production out of the side panels.. the 400w ones. I have tested each panel with a meter and they all put out about 42 volts. The panels are tilted at about 41 degrees now too. Today they did ok.. but were limited by the 45a controller. They are back in 2s2p and connected to the 150\100. I can swap the 400's with 4 of the 290 and see if that helps.

Can 8awg PV wires handle 50A..? ok.. I'll connect a pair of the 290's with the 400's. 2s3p.. and post up with an update soon after I know.
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Wow.. your system is so stable... unlike mine.. the voltages drop to 40 and jump to 90..

 

[MisterSandals]

Can 8awg PV wires handle 50A..? ok.. I'll connect a pair of the 290's with the 400's. 2s3p..

Where are you getting 50A?
With 3P (as you insist) that would be 7.97A + 9.74A + 9.74A = 27.45A

This is easily handled by 10AWG in reasonable lengths.

 

[MisterSandals]

I think it's in the 10awg wires.. BOTH pv and the wires that go to the batteries.

10 AWG is plenty for your array. Its clearly less that 30A for 3P array (sum of parallel Imp strings).

But with 4x 400W, thats 1600W.
Assuming a 12V battery system:
1600W / 14V charging volts = 114A

I cannot tell how many watts your array is producing based on how it is configured but divide that by 14V to get your charging amps.
Here is a chart for recommended wire gauge.

I got your video to load and i am with you on your 4x 400W panels being 2S2P (this is a popular array config).

 

[sunshine_eggo]

Interesting indeed.. but it works.. but figuring out what's causing it to not work better is frustrating.. I think it's in the 10awg wires.. BOTH pv and the wires that go to the batteries.

10awg is typically only good for 30A, so you're pushing it if you have 10awg between MPPT and battery. With the 150/100, you want 2awg fine strand wire to get 100A.

I've tried to get anyone to come help me locally, but no success yet. So that 290w panel has been removed from the system. Yes.. it got a little morning sun but held back the others in the afternoon.

If the one panel was in parallel with 2S panels, it was killing afternoon production due to lower voltage.

So.. from here on out I want to get more production out of the side panels.. the 400w ones. I have tested each panel with a meter and they all put out about 42 volts. The panels are tilted at about 41 degrees now too. Today they did ok.. but were limited by the 45a controller. They are back in 2s2p and connected to the 150\100. I can swap the 400's with 4 of the 290 and see if that helps.

Again, 10awg is too thin between MPPT and battery.

Can 8awg PV wires handle 50A..? ok.. I'll connect a pair of the 290's with the 400's. 2s3p.. and post up with an update soon after I know.

Depends on the insulation rating. 200° Silicone wire can handle 80A, but it gets warm. 75°C or better wire can handle 50A

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Wow.. your system is so stable... unlike mine.. the voltages drop to 40 and jump to 90..

Arizona sun. High desert. Thin air (more sun). No shade all day. Pretty much the opposite of your situation.

Note 5 days ago... 3121W. My array is only rated for 2970.

Where are you getting 50A?
With 3P (as you insist) that would be 7.97A + 9.74A + 9.74A = 27.45A

This is easily handled by 10AWG in reasonable lengths.

I had mentioned 50A if he went 5P.

 

[Pi Curio]

They ARE currently in 2s2p config.. It's 2:48 pm now..

​

 

[SeaGal]

Your too funny..

I try

So.. How many do you see..? and how many security cameras do you see..

Just the 2 in that pic... but your SWMBO told me you put one in the bedroom too

 

[Truck driver]

I try


Just the 2 in that pic... but your SWMBO told me you put one in the bedroom too

3.. All outside.. and none peeking\looking in. the tree, the Jeep and the trailer. lol.. SWMBO..?

 

[Truck driver]

10awg is typically only good for 30A, so you're pushing it if you have 10awg between MPPT and battery. With the 150/100, you want 2awg fine strand wire to get 100A.



If the one panel was in parallel with 2S panels, it was killing afternoon production due to lower voltage.



Again, 10awg is too thin between MPPT and battery.



Depends on the insulation rating. 200° Silicone wire can handle 80A, but it gets warm. 75°C or better wire can handle 50A



Arizona sun. High desert. Thin air (more sun). No shade all day. Pretty much the opposite of your situation.

Note 5 days ago... 3121W. My array is only rated for 2970.



I had mentioned 50A if he went 5P.

Thanx for the detailed reply.

 

[MisterSandals]

SWMBO

(humorous) Initialism of she who must be obeyed: one's wife or female partner.(Noun)

 

[Truck driver]

(humorous) Initialism of she who must be obeyed: one's wife or female partner.(Noun)

Well.. It's my unfortunate luck or timing.. but there is no wife or female partner in my life.

So.. I've called all or most of the big solar install companies in my area and nobody wants to install or let alone help with my system and it's issues. They claim it's a liability issue. I think if I offered them 10k, there'd be someone out here in a day or two. IDK.. So is there anyone I can call for phone tech support..? I'm getting frustrated trying to make this system work at it's full potential. I have both arrays connected and seemed to work well today..
12v
1st array : 3*400w in series. produced 572W 2.28KWh 133.59v maybe 5 degree tilt
2nd array: 6*290 in 3s2p. produced 411W 1.57KWh 115.81v flat on ground (on blocks)

combined power made today (and still going) 3.7 KWh 3740W total.

 

[Truck driver]

Ok.. I'm glad I had the 3 in 1 branch connectors. Both arrays are now in parallel. We'll see what difference it makes. total for today was 3.9 KWh.

 

[sunshine_eggo]

Well.. It's my unfortunate luck or timing.. but there is no wife or female partner in my life.

So.. I've called all or most of the big solar install companies in my area and nobody wants to install or let alone help with my system and it's issues. They claim it's a liability issue. I think if I offered them 10k, there'd be someone out here in a day or two. IDK.. So is there anyone I can call for phone tech support..? I'm getting frustrated trying to make this system work at it's full potential. I have both arrays connected and seemed to work well today..

You've got several competent people engaged, so I'm confident you will get a correct answer in the end.

Given your shading situation, I'm pretty sure you're going to be dining on solar shit sandwiches daily.

I know it's been mentioned that the panels need to be raised off the ground to prevent shading. Has that been done? Shade can be devastating. Simply shading the bottom row of cells as indicated here:



would nearly cripple the entire bottom half of each panel even in full sun, so if you haven't gotten them off the ground, do it.

If there is a time of day where each panel is in full sunlight, blackout (cardboard or opaque blanket) the other panels and evaluate them individually.

If you have a clamp DC ammeter, you can skip the blackout shading and simply measure the output current of the panel on the wire and compare that to the Imp rating.

You're getting the equivalent of about 2.5 solar hours per day. Given your shading issues, that sounds pretty good to me.

 

[SamDeleted]

You're getting the equivalent of about 2.5 solar hours per day. Given your shading issues, that sounds pretty good to me.

That's what I was thinking, it sounds about right in shade