Help with Low Amps

[kfergrocks]

Hello friends,

I'm looking for assistance "debugging" my recent setup. I am not getting nearly the power output I was expecting.

Attached is my approved-by-Solark wiring diagram of the system.
Also attached is a picture of the the array taken at 12noon on a sunny day.

I have two Solarks AIO Inverters setup in parallel. Each Solark has 3 MPPT controllers and each controller can handle 2 strings.

I have 5 strings of panels. Each string has 9 panels in series. There are 4 Tigo TS4-A-2F in between every set of 2 panels and 1 Tigo for the last.
There is ~300ft of 8awg wire from panels to Solarks.

Master MPPT-1 has 2 strings in parallel (using an mc4 Y connector - I only have 4 sets of pos/neg wires running from field to house.)
All other MPPTs have 1 string each.
Safety voltage at the inverter read 2.9V (which according to Tigo is exactly what it should be) for each string.
Once the TIGOs were activated and with no load on the Inverters - all strings were reading ~330V at Solarks.

Each individual panel's ratings:

• VOC - 38.97V
• ISC - 9.41A
• VMP - 31.67
• Imp - 8.84A

For (String 1 in parallel w/ String 2) the expected ratings:

• VOC - 350V
• ISC - 18.82A
• VMP - 285
• Imp - 17.68A

For all other strings

• VOC - 350V
• ISC - 9.41A
• VMP - 285
• Imp - 8.84A

Below are under load readings at 12noon in full sun.
Master Solark

• MPPT-1 (1&2 from front)
  • Volts - 273V
  • Amps - 4.1A
• MPPT-2 (3rd from front)
  • Volts - 281V
  • Amps - 2.0A

Slave Solark

• MPPT-1 (4th from front)
  • Volts - 269V
  • Amps - 2.3A
• MPPT-2 (5th from front)
  • Volts - 281V
  • Amps - 4.4A

Master Solark Power Readings
Solar power - 1.69KW
Grid power - 4.57KW
House Load - .79KW
Battery Load - 5.05KW

Slave Solark Power Readings
Solar power - 1.86KW
Grid power - 4.74KW
House Load - .9KW
Battery Load - 5.48KW

Any thoughts as to why my power output is ~25% of the max? Would the winter shadows be causing that much of an impact?

 

[SamDeleted]

Any thoughts as to why my power output is ~25% of the max? Would the winter shadows be causing that much of an impact?

Yes you've hit the nail on the head , 25% is a good figure with that heavy shading.

 

[kfergrocks]

ouch - thank you for confirming by upsetting suspicion.

Any idea if this device would help at all?
Sol-Ark O900-80V RSD and Module Optimizer for SA-12K & SA-15K Inverters

 

[SamDeleted]

ouch - thank you for confirming by upsetting suspicion.

Any idea if this device would help at all?
Sol-Ark O900-80V RSD and Module Optimizer for SA-12K & SA-15K Inverters

Maybe a bit , but really, solar panels need direct sunlight to produce any power

This device would significantly improve solar production ?

Robot or human?

(plus it's electric so you can charge off solar ? )

 

[kfergrocks]

haha - I was seriously contemplating having the trees trimmed earlier today - but was hoping (apparently fruitlessly) I was missing something else in my setup. Thanks for the help.

 

[SamDeleted]

haha - I was seriously contemplating having the trees trimmed earlier today - but was hoping (apparently fruitlessly) I was missing something else in my setup. Thanks for the help.

Cut the bush or move the panels ?

 

[MisterSandals]

I have 5 strings of panels. Each string has 9 panels in series.

I suspect that your strings are in rows from left to right in your pic. This looks like the shade will progress from one side to the other during the day and almost always have some shade within every string.
If your strings had 9 panels on the very left (2 in each of 4 rows, 1 in one of the other rows to make a 9 panel series string) then that "column string" would be good. If you arranged your other 4 strings similarly it would likely be better.

Not an easy thing to test since you'd need a lot of connector cables.

 

[kfergrocks]

I suspect that your strings are in rows from left to right in your pic. This looks like the shade will progress from one side to the other during the day and almost always have some shade within every string.
If your strings had 9 panels on the very left (2 in each of 4 rows, 1 in one of the other rows to make a 9 panel series string) then that "column string" would be good. If you arranged your other 4 strings similarly it would likely be better.

Not an easy thing to test since you'd need a lot of connector cables.

Interesting idea - very clever - Thank you