I have some dumb questions about circuit breakers and saftey

[73powerstroke]

I've basically been running an experimental setup modifying it as I go along and I don't ever leave it unmonitored or unmanned. But I've come to the point that I don't want to shut everything down every time I leave the house so I ordered some circuit breakers and things like that and started to try and protect the system so that they would not be any possibility of casualties.
I also realized that I had some issues with some poor mc4 connectors and heating and melting problems so I've had to make some changes and I'm pretty sure I'm doing a few things wrong here.
I have 14 panels (240w) going to a hvlv2424 inverter
I have everything 2 series. Would prefer 3s but its too close to the inverters limits
So 2s it is. One group of panels is 2s2p using cheap branch connectors and a 30 foot 10ga pv run. Combined to another 2s2p group in a different direction. The panels short circuit current is 8.37a per panel. The other group is 2s3p using branch connectors also with its own 10ga pv run. These all come together to a 63a santan solar (polarized? ) 63a mcb . A different group of panels 2s3p are also feeding the inverter independently.
How do i make this safe? I have a 150a battery circuit breaker but it was getting hot. So i removed it. Its also from santan solar

 

[MisterSandals]

A different group of panels 2s3p are also feeding the inverter independently.

How can they feed an inverter independently? Are they switched or in parallel (not independent)?

3P strings need to have fuses on each string.

I have a 150a battery circuit breaker but it was getting hot.

What passes thru this breaker? Charge or load? How many amps?
Both? If so, is it a bi-directional breaker?

 

[Supervstech]

How can they feed an inverter independently? Are they switched or in parallel (not independent)?

3P strings need to have fuses on each string.

What passes thru this breaker? Charge or load? How many amps?
Both? If so, is it a bi-directional breaker?

I'm guessing he has multiple charge controllers...

 

[Mattb4]

I must admit I am struggling to understand your PV setup. Some further detailing of components would help.

Considering connecting things up safely. Likely you are at the point a multistring combiner box would be a good approach. It will have fuses and a disconnect breaker.

 

[MisterSandals]

I'm guessing he has multiple charge controllers...

I have 14 panels (240w) going to a hvlv2424 inverter

"a" (i won't get into the grammar :*) ).

I dunno. The array description in not clear.

 

[73powerstroke]

How can they feed an inverter independently? Are they switched or in parallel (not independent)?

3P strings need to have fuses on each string.

What passes thru this breaker? Charge or load? How many amps?
Both? If so, is it a bi-directional breaker?

Parallel 2 sets of wires into inverter

 

[73powerstroke]

I'm guessing he has multiple charge controllers...

Im only using the mpp solar hv lv2424

 

[MisterSandals]

Parallel 2 sets of wires into inverter

So you have quite a few parallel connections!



2S3P ---------------- \ ---------- (2S7P) --------- inverter?
2S2P ----> \ ---------- (2S4P) ----------------- /
2S2P ----> /

The panels short circuit current is 8.37a per panel.

come together to a 63a santan solar (polarized? ) 63a mcb

7 x 8.37A = 59A this will run hot and be subject to nuisance trips
10AWG suitable for 30A in short runs. You need a bit more after combiner box and even more after combining to 59A before inverter.

I am not sure how many fuses you need in your array. (f)
My guess:
2S3P ---------------- (f) \ ---------- (2S7P) --------- inverter?
2S2P ----> (f) \ ---- (2S4P combiner box) --------------(f) /
2S2P ----> (f) /

I think with a 4 array combiner box, put a 2S2P, 2S2P and (2S3P (with 3 fuses)) into it. Each input should have a breaker or fuse. Out of combiner you will need to handle 59A x 1.56 for the distance involved.

 

[Mattb4]

If you only have one SCC you are likely running a 2S7P setup. This would give you a potential of 7 times your panels current rating (Imp) to have to handle. Your AIO limits this by its max charge rating. It will not pull more than it can put out.

 

[MisterSandals]

Your AIO limits this by its max charge rating.

(14 x 240W) / 28V charging = 120A charge current available from the array. I'm thinking this is a lot of over paneling!

 

[73powerstroke]

 

[73powerstroke]

(14 x 240W) / 28V charging = 120A charge current available from the array. I'm thinking this is a lot of over paneling!

These panels rarely produce more than 150 each. Real world. I never see over 2kw

 

[MisterSandals]

Thats 18 panels in your drawing.

Does your SCC have 2 MPPTs or how does it accept 2 arrays as drawn?

 

[73powerstroke]

If you only have one SCC you are likely running a 2S7P setup. This would give you a potential of 7 times your panels current rating (Imp) to have to handle. Your AIO limits this by its max charge rating. It will not pull more than it can put out.

Yes. But the way they are joined together is my concern. And i forgot to add the other 2s3p array that parallels at inverter lol ?
So the 2s3p group has its own 10ga pv wire run to inverter. In attempt to stay under 30a or the rated limit of 10ga pv wire.
The 2s2p group parallels with the other 2s2p group before making a run to inverter. The 3rd 2s2p group has its own run also.
I know its confusing. Im trying to not leave out anything. My diagram should help

 

[73powerstroke]

Thats 18 panels in your drawing.

Does your SCC have 2 MPPTs or how does it accept 2 arrays as drawn?

The hvlv2424 is a 80a mppt . Ive just paralleled the input fitting the wires in there

 

[73powerstroke]

Maybe i should make a video of everything and upload it to my YouTube
Since i know this is quite confusing

 

[MisterSandals]

These panels rarely produce more than 150 each.

Not sure how one "legally/safely" wires for degraded panels.

In attempt to stay under 30a or the rated limit of 10ga pv wire.

Very little of this is wired for 30A. Technically, this is 2S9P and short circuit potential back to the array is (9x 8.37A)= 75A. This is a fire hazard in the mildest term that is still correct.

Since i know this is quite confusing

I think i get it.

You NEED a 4-6 string combiner box with at least a 120A main. Then fusing for your 4 parallel arrays. Then a wire that handles 75A x 1.56 = 118A from your combiner to SCC.

What is the max fuse rating listed on your panels?

 

[Mattb4]

Likely you will want combiner boxes for combining those strings that have 3P. These combiners can than feed your main combiner. The idea being to avoid two many Y connectors. It is either this or have more SCC and split your array into several.

 

[73powerstroke]

Not sure how one "legally/safely" wires for degraded panels.


Very little of this is wired for 30A. Technically, this is 2S9P and short circuit potential back to the array is (9x 8.37A)= 75A. This is a fire hazard in the mildest term that is still correct.


I think i get it.

You NEED a 4-6 string combiner box with at least a 120A main. Then fusing for your 4 parallel arrays. Then a wire that handles 75A x 1.56 = 118A from your combiner to SCC.

What is the max fuse rating listed on your panels?

Should i just start from scratch? It seems like it. Maybe if every group of panels has its own run to a combiner box. Im about 40 to 60 feet away from the aio inverter.
Max fuse rating is 15a

 

[73powerstroke]

Likely you will want combiner boxes for combining those strings that have 3P. These combiners can than feed your main combiner. The idea being to avoid two many Y connectors. It is either this or have more SCC and split your array into several.

I do have 3x 40amp cc i can use.