Help! Newcomer needs advice!

[MisterSandals]

It appears that I would have to get different branch connectors (three 'doubles' instead of using two 'triple' branch connectors) correct.

I am not sure what your array config will be so it’s way too early to talk about connectors.

I thought that the 150 part of the 150/50 was the specific to 24v PV system?

The 100/50 and 150/50 both can work with 12V or 24V battery systems.
They are limited/spec’d by their number/sizing designations: max input voltage / charging amps.

 

[MisterSandals]

The cost of three 75/15s isn't unreasonable compared to the astronomical price of a large SCC.

This is very true. If you are stuck with and limited to these 3 panels, this may be your best option.

If you can get 1 more panel and a 150/50 (or better still, 150/70), which can handle the voltage of 2 panels in series, twice in parallel, you can have a 2S2P array. This is a GREAT solution.
You only need 1 pair of Y connectors and no fuses. This is what I would do!

With 1000W / 14V charging = 71A max charging (you won’t get this with flat mounted panels, but this is perfect!!! For size, not running at 100%).

This would be REALLY good.

 

[Oak_Sandalfoot]

This is very true. If you are stuck with and limited to these 3 panels, this may be your best option.

If you can get 1 more panel and a 150/50 (or better still, 150/70), which can handle the voltage of 2 panels in series, twice in parallel, you can have a 2S2P array. This is a GREAT solution.
You only need 1 pair of Y connectors and no fuses. This is what I would do!

With 1000W / 14V charging = 71A max charging (you won’t get this with flat mounted panels, but this is perfect!!! For size, not running at 100%).

This would be REALLY good!

I've been researching and getting to know all of the details you've laid out for the better part of the day and I'm starting to feel more confident about moving forward with your suggestion of 4 panels in 2s2p configuration.
I just can't get over the fact that a reputable solar company (SanTan Solar) would allow me to walk out the warehouse door with the impression that I could wire these in three panels in series and still use the 100/50 MPPT they also sold me. I'm going to sort all this out over the phone tomorrow. Hopefully I can get a discount for the inconvenience. ?
Huge thanks for all of your input, Mister Sandals! G' night!

 

[Oak_Sandalfoot]

150V max input. Your panels have a Voc over 50. You could put 2 in series but cannot use your 3rd panel.

You could use 4 panels, 2S2P (just over 100V, 2x the Vmp).

How about some panels that will allow you to run 3 in series with a 150/50? Or for a 4th panel like you have and a 150/50.

I just talked to the solar consultant and he said that if I wired all three panels in parallel that the 100/50 would be fine. I must have mistaken series for parallel. Does this check out?

 

[MisterSandals]

I currently have all three panels fused (15a or 30a, whatever they sold me with the panels) before they enter the solar cable gland.

Each panel, when 3 or more in parallel needs to be fused. What is the Isc of your panels? Is there a max fuse size number on your panels?

This needs to be done just before combining in parallel (3:1 connector?). Are the fuses inline MC4 or ??

if I wired all three panels in parallel that the 100/50 would be fine.

750W / 14V = 53A
Panels mounted flat won't produce 100% so 50A seems good.

 

[Oak_Sandalfoot]

Each panel, when 3 or more in parallel needs to be fused. What is the Isc of your panels? Is there a max fuse size number on your panels?

This needs to be done just before combining in parallel (3:1 connector?). Are the fuses inline MC4 or ??

750W / 14V = 53A
Panels mounted flat won't produce 100% so 50A seems good

Each panel, when 3 or more in parallel needs to be fused. What is the Isc of your panels? Is there a max fuse size number on your panels?

This needs to be done just before combining in parallel (3:1 connector?). Are the fuses inline MC4 or ??

750W / 14V = 53A
Panels mounted flat won't produce 100% so 50A seems good.

Series Fuse Rating = 20A
Yes, the three (-) and (+) solar cables each combine into their own branch connectors where they are fused between between all the (+) MC4 connectors.

They definitely sold me a kit that is intended to be wired in parallel yet somehow I thought series...d'oh!

I guess I'm back to the point where I can move on with confidence and start mounting my components!

 

[Oak_Sandalfoot]

Series Fuse Rating = 20A
Yes, the three (-) and (+) solar cables each combine into their own branch connectors where they are fused between between all the (+) MC4 connectors.

They definitely sold me a kit that is intended to be wired in parallel yet somehow I thought series...d'oh!

I guess I'm back to the point where I can move on with confidence and start mounting my components!

*Correction: 15A Fuse Rating