48V 6kW Growatt Split-Phase 240v 80AMPPT w/battery 48V KONG 233Ah

MPRanger

Beefield, GA 30461
Joined
May 21, 2021
Messages
134
Location
Beefield Georgia
I already have running here at the farm a Fronius 6kWh grid-tied system. I purchased 20 panels from SanTan Solar as mentioned in Will's video https://store.santansolar.com/product... I wish to use all 20. Here is a detailed photo from the back of that panel.
55C3AA0B-A300-4E5F-A713-41A44A0D3302_1_105_c.jpeg1628205841006.png

I purchased a Growatt SPF 6000 DVM split-phase 48V6kW. Here's the info from the side of it:

E6F0F285-7FC3-4505-B6A7-E7A087D95B7C_1_105_c.jpeg

And lastly, I purchased a Bigbattery KONG 48V LiFePO4 12kWh 233Ah.

Now the maths start. You see I can not exceed 150V input from the PV and each panel puts out 30.6V @PMAX and 368.2V at open circuit.

So I have PV Y connectors and Tri connectors and of course can buy others like the MC4 T Branches. But alas how to reach the MAX wattage without exceeding the MAX 150V. Then how to use all 20 panels.

I'm open for input as I continue I will share photos and comments, experiences, and gripes.

Ranger
 
Last edited:

MPRanger

Beefield, GA 30461
Joined
May 21, 2021
Messages
134
Location
Beefield Georgia
So I have computed the number of panels allowed in a string and I have that as 4. There Is a single PV insert on the inverter.
60/30.6=1.96 minimum panels is 2
145/30.6=4.74 Max panels is 4
So next how many strings in parallel
 

MPRanger

Beefield, GA 30461
Joined
May 21, 2021
Messages
134
Location
Beefield Georgia
Any time I construct something on the farm here I must be observed by the cats. One such cat not pictured here I call "Cat-dog" because he does not believe he is a cat. He seems to think he's a dog including begging, following me around and chasing anything furry that moves.97848B04-A670-429D-9FDC-F46E22E7C100.JPG
 

MPRanger

Beefield, GA 30461
Joined
May 21, 2021
Messages
134
Location
Beefield Georgia
Alas, I made a poor decision purchasing my inverter from an e-Bay seller (bjjiabaokuser ). I looked at this seller's other items and there appears to be a large amount of sexual or healthcare items in that inventory and NOT a whole lot of solar. My contact with this seller was made on the day the product arrived and the seller asked for 24 hours to contact his technical staff. Twenty-four plus hours have passed with no further contact so I began a return. This thing weighs a good 70 pounds so shipping is going to be a couple hundred dollars that I will not get back. I paid the shipping to get it, this amount might be returned to me via e-Bay and PayPal. Lesson: do not buy from e-Bay unless it's a solar retailer.
 

Roqm

Solar Enthusiast
Joined
Jun 17, 2020
Messages
201
Alas, I made a poor decision purchasing my inverter from an e-Bay seller (bjjiabaokuser ). I looked at this seller's other items and there appears to be a large amount of sexual or healthcare items in that inventory and NOT a whole lot of solar. My contact with this seller was made on the day the product arrived and the seller asked for 24 hours to contact his technical staff. Twenty-four plus hours have passed with no further contact so I began a return. This thing weighs a good 70 pounds so shipping is going to be a couple hundred dollars that I will not get back. I paid the shipping to get it, this amount might be returned to me via e-Bay and PayPal. Lesson: do not buy from e-Bay unless it's a solar retailer.
It sounds more like the inverter isnt a good march for your panels( which ever you got first panels or inverter) now that you have your panel specs you can better match a inverter or mppt controller for your instal.
 

MPRanger

Beefield, GA 30461
Joined
May 21, 2021
Messages
134
Location
Beefield Georgia
3-4 panels in ea string with strings in parallel would work, but the inverter out of the box will not power on with just three panels in a string. The inverter simply doesn’t power on at all.
 

MPRanger

Beefield, GA 30461
Joined
May 21, 2021
Messages
134
Location
Beefield Georgia
It sounds more like the inverter isnt a good march for your panels( which ever you got first panels or inverter) now that you have your panel specs you can better match a inverter or mppt controller for your instal.
I had the panels first. And yes, the inverter is not the best match for these panels with a max input of 145V. The system is designed for off-grid only with battery storage. After opening the cas, it had a loose connection inside on the 48v input. The inverter must have the battery power the system to turn on. So, even though I had properly connected 240V AC and the Anderson connection to the external ports, AC doesn’t power anything and the loose dc connection was only passing fewer than 5V. Anyhow I now have a system that can power the barns. I just need to install another power panel that isn’t grid tied and move some wires. AND I need to find math help to figure best way to use what I’ve got.
 

TomC4306

Solar Addict
Joined
Mar 2, 2021
Messages
202
2s panels are marginally inadequate voltage.
4s panels are too high voltage.
VOC < 150
4 panels x 38.2 =152.8.
And more like 175v when it's cold.

With these panels and those scc specs, the only config that I can see fitting is 3s6p. Or buy one more panel locally off craigslist and go 3s7p.
 

MPRanger

Beefield, GA 30461
Joined
May 21, 2021
Messages
134
Location
Beefield Georgia
Cold…. I live in SE Georgia where the 25 year low was 25°F overnight. Have Not experienced a day in 25 years where by the sun directly over the fixed panels would suffer less that 35°F. So, yes three panels. And how many parallel can I squeak into the equation? I can get combining box.

I don’t understand what panels are on the market have high-wattage and with low voltage. An inverter that says 150 V max. It is created with 220V out you’d think there would be some room somewhere to support 1000V in. I’m looking at an Outback smart grid but alas it doesn’t support high PV voltage either. As time moves forward these PV are sure to have higher watts and volts too, yes?
 
Last edited:
Top