Please help: Solar panel setup for Ecoflow smart panel and Delta Pro

[kenfused]

Following...
I was thinking about using EcoFlow delta (or a diy setup) with 2S2P setup with 4 panels. 260W used REC panels,

Open Circuit Voltage (V)	37.8
Short Circuit Current (A)	9.01

If I did math right, 76V and 19 A = 1444w, or at 15 A max 1140w
or is 3 panels almost the same if I did 3S = 114v x 9A = 1026w
Does this sound right, and is it an efficient setup to charge the EcoFlow Delta Pro?

 

[Bud Martin]

Following...
I was thinking about using EcoFlow delta (or a diy setup) with 2S2P setup with 4 panels. 260W used REC panels,

Open Circuit Voltage (V)	37.8
Short Circuit Current (A)	9.01

If I did math right, 76V and 19 A = 1444w, or at 15 A max 1140w
or is 3 panels almost the same if I did 3S = 114v x 9A = 1026w
Does this sound right, and is it an efficient setup to charge the EcoFlow Delta Pro?

Vmp x Imp = Panel Wattge.
What is the Vmp and Imp?
The one to watch out for is the Voc, it should not exceed the max PV input Voltage of the Ecoflow.

 

[kenfused]

• Imp 8.5A
• Vmp 30.7V

 

[Bud Martin]

• Imp 8.5A
• Vmp 30.7V

So with 2s2p setup:
Vmp = 30.7V x 2 = 61.4V
Imp = 8.5A x 2 = 17A
Total power = 61.4V x 17A = 1043.8W
Since the max input current is limited to 15A, then you will get 61.4V x 15A = 921W

 

[Tym]

Panel Wattage = Vmp x Imp
3S so total Voc = 21.6V x 3 = 64.8V (total Vmp = 18V x 3 = 54V), so that is correct. Are you expecting to get a lot more than 70V?
Isc for 3 strings in parallel = 10.5A x 3 =31.5A (Imp = 10A x 3 = 30A
So no way the Solar generator will be drawing 1600W from your panels because it has 15A max PV input current, so 54V x 15A = 810W.
Since the max input current is limited to 15A (the solar generator is only allowed to draw 15A from the panels even if your source can provide more than 15A), so to get more power from your panels, you can do:
Notes: Since Voc of the panel goes up when cold, so I would factor in about 15% less than the max Voc input rating of the solar generator, so 150V x 0.85 = 127.5V
6s which will have total Voc of 21.6 x 6 = 129.6V (close enough), Vmp = 18V x 6 = 108V, 108V x 10A = 1080W, the other 3 panels will not be used.
4s2p will give you 18V x 4 x 15A = 1080W
So as you can see, due to 15A limit, your panel spec, and the quantity of the panels you have, you will not get 1600W that you want, you have to find the right combination of Vmp multiply that by 15A limit to achieve the max Wattage.

 

[Tym]

Amps and watts don’t matter per EcoFlow. Only volts. Briefly today was over 1000 W with my nine panel set up. Laying flat with a slight degree to the north. At 10:30 AM in north Florida. Too much math going on here. All I do is put a voltmeter on the input wire from the panels to the EcoFlow and reading only 70 V. Just think what I can do with them being tilted towards the south. Averaging 940 W at 12:33 PM now.

 

[Bud Martin]

Amps and watts don’t matter per EcoFlow. Only volts. Briefly today was over 1000 W with my nine panel set up. Laying flat with a slight degree to the north. At 10:30 AM in north Florida. Too much math going on here. All I do is put a voltmeter on the input wire from the panels to the EcoFlow and reading only 70 V. Just think what I can do with them being tilted towards the south. Averaging 940 W at 12:33 PM now.

Your Post #16:
"I have nine 180 W Bouge RV panels connected in series and parallel to one delta pro. And only pull in 70volts."
You were expecting more than 70V with your 3s3p panel arrangement.
Well math does not lie and you see why you are not getting more than 70V, it is good to understand the math to use the product at it highest capability, you can do 2s2p to get the same 1000W as the 3s3p you have now. How do you think you get 1000W with 70V without using the current for calculation?
The input current limit of the Ecoflow/Blueti (I also have Bluetti, it has 8A input current limit)/Jackery does have affect on how much power you can get, it is the combination of V and I.
You are getting 70V and if you check the input current, it will be about 15A even if your 3s3p can deliver up to 30A, 70V x 15A = 1050W.
So using 3s3p is not efficient, 2s2p will still allow you to have 70V and 15A = 1050W, if the current is not limited by Ecoflow to 15A then you would have get a lot more power from your 3s3p. You can use the 3 extra panels for something else, or arrange the 3 strings of panels in 3 directions so they will collect the power at longer period of the day.
You can easily check the panel current with the DC clamp on meter, it is a good tool to have.
P = V x I
Solar panel is the power source, Ecoflow is the load that will draw up to 15A max from the source by design, current is not pushed into the load, the load draw current from the source. These solar generator has input current limit so it will not damage or draw too much current from the charging source, for example when you try to charge from the cig lighter, if there is no current draw limit, it will draw more than 15A which will blow the fuse of that cig lighter.

 

[Tym]

OK. I don’t claim to know everything but I will disconnect three panels and see what their output is. I also have these nine panels laying flat. And are not bolted down. I know I can get more wattage if I angle them towards the sun, but I am concerned about the wind. Although not too much wind here in Florida.

 

[Tym]

I thought the more panels I added, the more volts they would produce?

 

[Bud Martin]

I thought the more panels I added, the more volts they would produce?

Panels in series = Voltage are added, current stay the same.
Panels in parallel = Voltage stay the same, current are added, for examples:
Panel has Vmp of 18V, Imp of 5A: so putting 3 panels in Series, you will have the total Vmp will be 18V x 3 = 54V, the current will stay at 5.5A.
Panel has Vmp of 18V, Imp of 5A: so putting 3 panels in Parallel, you will have the total Vmp will be 18V, the current will be 5.5A x 3 = 16.5A.