My solar panels have high voltage--how many can I fit on a Deye?

[Fisto]

I bought some 550w Longi panels that are 49.95 volts each.

I plan to use them with a Deye 8KW inverter, whose voltage range is 150 to 425.

It seems like I'd only be able to fit 8 panels in that voltage range which would only give me 4400 watts, less than half what I intended to hookup.

Am I calculating this correctly?

 

[FilterGuy]

You are doing the math correctly but you are leaving a couple of important things that must be considered.

1) Voltage increases in cold weather.
Depending on the Voc temperature coefficient and the temperature extremes in your area, you may not be able to do 8 panels without the danger of burning out the solar controller.

Adjusting Solar Panel Voc for temperature

When designing you solar panel system, it is important to adjust you solar panel Voc for temperature in order to ensure you do not over-voltage the PV inputs of your solar charge controller. This paper shows how to calculate the Temperature...

diysolarforum.com

2) Multiple MPPT units.
As I recall, the Dye has two MPPT trackers so you can put two separate arrays on the unit

3) Multiple Parallel strings.
Check the max Isc of the dye. If it is high enough, you may be able to put two strings in parallel on each of the MPPT controllers.

 

[Fisto]

You are doing the math correctly but you are leaving a couple of important things that must be considered.

1) Voltage increases in cold weather.
Depending on the Voc temperature coefficient and the temperature extremes in your area, you may not be able to do 8 panels without the danger of burning out the solar controller.

Adjusting Solar Panel Voc for temperature

When designing you solar panel system, it is important to adjust you solar panel Voc for temperature in order to ensure you do not over-voltage the PV inputs of your solar charge controller. This paper shows how to calculate the Temperature...

diysolarforum.com

2) Multiple MPPT units.
As I recall, the Dye has two MPPT trackers so you can put two separate arrays on the unit

3) Multiple Parallel strings.
Check the max Isc of the dye. If it is high enough, you may be able to put two strings in parallel on each of the MPPT controllers.

1). I couldn't understand your link at all about Voc temperature coefficient. The ambient temperature where I live is 80-85 degrees.

2). The Deye has two strings per MPPT tracker.

3). The Deye's max ISC is 44A+44A.

 

[FilterGuy]

1). I couldn't understand your link at all about Voc temperature coefficient. The ambient temperature where I live is 80-85 degrees.

As the temperature goes below 25deg C, the Voc will go above the spec value. In order to ensure you do not over-voltage the MPPT controller, you will need to calculate the voltage rise for the lowest temperature the panels will experience. Most people use the coldest historical temperature for their location to do the calculation.

The amount of voltage rise will depend on the Beta (Voc Temperature coefficient) of the panel. In the back of the document there are tables with Beta across the top and temperature down the side. Use the Voc Temperature Coefficent of the panel and the lowest temperature for your area to get a multiplier. Use the multiplier on the Voc in order to determine the highest Voc for your location.

2). The Deye has two strings per MPPT tracker.

3). The Deye's max ISC is 44A+44A.

As long as the Isc of your panel is less than 22A, you should be able to get two strings on each MPPT controller.

 

[Danke]

I hear Deye is similar to Sol-Arks. Here is a link for Sol-Arks to play with. I only see Longi up to 540W, but you can manually change the watt number.

Solar Panel Sizing 4.5

www.sol-ark.com

 

[Joehebbo]

You are doing the math correctly but you are leaving a couple of important things that must be considered.

1) Voltage increases in cold weather.
Depending on the Voc temperature coefficient and the temperature extremes in your area, you may not be able to do 8 panels without the danger of burning out the solar controller.

Adjusting Solar Panel Voc for temperature

When designing you solar panel system, it is important to adjust you solar panel Voc for temperature in order to ensure you do not over-voltage the PV inputs of your solar charge controller. This paper shows how to calculate the Temperature...

diysolarforum.com

2) Multiple MPPT units.
As I recall, the Dye has two MPPT trackers so you can put two separate arrays on the unit

3) Multiple Parallel strings.
Check the max Isc of the dye. If it is high enough, you may be able to put two strings in parallel on each of the MPPT controllers.

Why not use 6 in series and anothe 6 in series and then combine them ++ and - - and then put them on one mppt it worse with me and if want add more panels can make more panels but in parallel like 7 in series and 7 or 8 in parallel doesn t work?

 

[Muzzammild36]

I have a 5kW Deye.
I have 9 X 365W panels on one of the MPPTs, my question is can I over panel by adding 1 of 365W panel to make it 10 X 365W panel on one of the MPPT, I will still be below the 500V VoC.
I have 5 X 550W panels on the other MPPT.


Can I over panel above the 3250W Provided I stay below the 500V VoC?

 

[HRTKD]

Can I over panel above the 3250W Provided I stay below the 500V VoC?

Yes, providing you take into account the temperature coefficient.

 

[Ampster]

Can I over panel above the 3250W Provided I stay below the 500V VoC?

Yes, provided you adjust voltage for the coldest day at your location.

 

[Muzzammild36]

Yes, providing you take into account the temperature coefficient.

My VoC for each panel is 41.59V+/- 3% and temperature coefficient should not be more than 1.1max as I am in tropical climate.

For 10 panels my voltage will be 471V, is that a safe voltage for 5kW Deye inverter?