HELP WITH SOLAR PANEL NUMBERS AND WIRING PLEASE

[Dr Danger Stunts]

I have a new Growat 12k and I am stuck trying to figure out how to correctly wire the panels in series parallel. I have 20 130 watt used panels. The max PV array open circuit voltage for the inverter is 250vdc and the PV array MPPT voltage range is 60-245vdc. There are two inputs for PV arrays. My brain is stuck trying to figure out which of the numbers on the back of the solar panel to use to calculate haw exactly to wire them up. I would like to know the best configuration for this please.

 

[Crowz]

Use the solar panel calculator in my signature to figure out how to combine them to get what you need.

 

[Dr Danger Stunts]

Use the solar panel calculator in my signature to figure out how to combine them to get what you need.

Thank you I will give that a try.

 

[Dr Danger Stunts]

Thank you I will give that a try.

Part of what is giving me trouble is I am still not sure what numbers on the panel to use. I cant tell which are the correct ones. It asks for VMP or VMPP and my panel only says Pmax, Vpmax, Ipmax, Voc and Isc. The next asks for Imp or Impp.

 

[Rocketman]

In a nutshell:

In series volts add… use lowest amps.
In parallel amps add use lowest volts.
Use Vmp and Imp for these calculations.

Voc - is max voltage when panels are not operating- first thing in the morning- this is the one that can fry your solar charge controller. We also need to know the lowest possible temperature at your location. (General location also helps - nearest big city). Because when it is cold the voltage rises.

Voc 21.9v
Vmp 17.6v
Imp 7.39a


In series if you put 10 panels in series you would have:
Voc 219v
Volts - 176v - Amps 7.39a
Depending on where you live this may be too many in series.
Can you get and use a few more panels? If that makes it better.

Also how many amps can the solar charge controller handle on the PV input?

 

[Crowz]

These are the ones your wanting from the picture you posted.
vmp 17.6
imp 7.39

 

[Dr Danger Stunts]

Thank you I will give that a try.

Part of what is giving me trouble is I am still not sure what numbers on the panel to use. I cant tell which are the correct ones. It asks for VMP or VMPP and my panel only says Pmax, Vpmax, Ipmax, Voc and Isc. The next asks for Imp or Impp.

 

[Crowz]

vpmax = vmp
ipmax = imp

 

[400bird]

vpmax = vmp
ipmax = imp

To help out the OP: the "m" in the right side set of acronyms is "max", as seen written out on the left.
Due to age and differences in how each company does things, they will often mix up the order of the acronym. Super confusing

 

[Dr Danger Stunts]

In a nutshell:

In series volts add… use lowest amps.
In parallel amps add use lowest volts.
Use Vmp and Imp for these calculations.

Voc - is max voltage when panels are not operating- first thing in the morning- this is the one that can fry your solar charge controller. We also need to know the lowest possible temperature at your location. (General location also helps - nearest big city). Because when it is cold the voltage rises.

Voc 21.9v
Vmp 17.6v
Imp 7.39a


In series if you put 10 panels in series you would have:
Voc 219v
Volts - 176v - Amps 7.39a
Depending on where you live this may be too many in series.
Can you get and use a few more panels? If that makes it better.

Also how many amps can the solar charge controller handle on the PV input?

120 amps for the MPPT input. Does this mean I can put 120 amps into each PV input on the inverter?

 

[Ampster]

120 amps for the MPPT input. Does this mean I can put 120 amps into each PV input on the inverter?

Yes, anything above it will be clipped. Voltage is the factor which you do not want to exceed. With only ten panels at 17.6 volts each you have plenty of headroom if your MPPT max voltage is 245 VDC

 

[400bird]

120 amps is the max total output at battery voltage. Not the PV input.

 

[zanydroid]

Looks like the answers here have been good so far.

I’m pretty confident the translation above between your specs sheet (written in arguably the equivalent of Old English, seeing as how it’s 17 years old) to modern English is correct.

 

[400bird]

120 amps for the MPPT input. Does this mean I can put 120 amps into each PV input on the inverter?

No
Let's do some math
The max MPPT voltage is 245 volts
245*120*2 = 58,800 watts
That would be an amazing inverter!

However, if we do the math for 120 amps output:
58 volts DC (high SOC battery voltage) * 120 amps = 6,960 watts
That's pretty close to the rated 7,000 watt PV array power.

 

[Dr Danger Stunts]

Yes, anything above it will be clipped. Voltage is the factor which you do not want to exceed. With only ten panels at 17.6 volts each you have plenty of headroom if your MPPT max voltage is 245 VDC

Thank you Kenny

 

[Dr Danger Stunts]

No
Let's do some math
The max MPPT voltage is 245 volts
245*120*2 = 58,800 watts
That would be an amazing inverter!

However, if we do the math for 120 amps output:
58 volts DC (high SOC battery voltage) * 120 amps = 6,960 watts
That's pretty close to the rated 7,000 watt PV array power.

I think I see what you are saying. I am going to be working on this again when I have the money for the combiner box and a few small things. I will probably have a few questions then. I have been building this setup since June and excited to get it going but trying to be careful and not rush it. Thank you

 

[YelowstoneRocks]

Use the solar panel calculator in my signature to figure out how to combine them to get what you need.

Sorry I'm so dense but I don't see your signature and would find your calculator very handy.

 

[400bird]

Sorry I'm so dense but I don't see your signature and would find your calculator very handy.

It's a dumb thing, turn phone sideways (horizontal) for the signatures to show up.