Have Deye 8Kw Inverter, but my panels exceed it

[Ampster]

hv 8 kw inverter using 12 pv 6 in series vs 6 other series producing like 5k to 6 k top should i go further to 8 pv each or 9 or it s risky

Hard to tell without actual Wattage of the panels. Series or parallel does not matter for the purposes of looking at DC to AC ratios. With an inverter capacity of 8kW you might go as high as 10 to 12kW in panels depending on location, orientation and tilt.

 

[LydMekk]

I

hv 8 kw inverter using 12 pv 6 in series vs 6 other series producing like 5k to 6 k top should i go further to 8 pv each or 9 or it s risky

What is the panels stats on the back?
STC VoC per panel?
If it is under 50V then no more than 8 in series per string. That would make it 400V and the MPPTs MAX is 425V charging.

 

[Joehebbo]

Hard to tell without actual Wattage of the panels. Series or parallel does not matter for the purposes of looking at DC to AC ratios. With an inverter capacity of 8kW you might go as high as 10 to 12kW in panels depending on location, orientation and tilt.

Panels are 545w longi with 40 v each direction south 29C beirut lebanon

 

[Joehebbo]

What is the panels stats on the back?
STC VoC per panel?
If it is under 50V then no more than 8 in series per string. That would make it 400V and the MPPTs MAX is 425V charging.

 

[Joehebbo]

This is the back voc 49.6
Stc 1.5

 

[Joehebbo]

This is the back voc 49.6
Stc 1.5

I believe there is a quantitative benefit to over panelling. Panels rarely produce their rated power and degrade over time. Higher DC to AC ratios mean that the inverter will be operating at optimum output more often. As mentioned earlier the amount lost to clipping is often a concern, but when calculated over time it is often very small.

but if one day they produce the maximum then you will be in over voltage

 

[Ampster]

but if one day they produce the maximum then you will be in over voltage

Not necessarily. Maximum voltage is predictable and avoidable. Adjust for lowest temperature and pick the correct number of panels in series and you can avoid any risk of over voltage. What is maximum voltage of your Inverter? Using that number, how many panels will your inverter safely take in series? You should use 49 volts per panel.

 

[Joehebbo]

Not necessarily. Maximum voltage is predictable and avoidable. Adjust for lowest temperature and pick the correct number of panels in series and you can avoid any risk of over voltage. What is maximum voltage of your Inverter? Using that number, how many panels will your inverter safely take in series? You should use 49 volts per panel.

My inverter 8kw deye single phase voc is 370Vdc (125 Vdc 500 Vdc) for input voltage and mppt is 150 Vdc 500 Vdc max imput power 10400w and max isc 28 Adv 28 Adc a picture is attached i m using 6 x 545 watts longi and another 6 x545 watts voc of 49.6 by panel where i can go to the max and still safe 8x8 or 9x9

 

[Ampster]

So what does the math tell you?
Here is a clue:
Calculate how many volts will 8 panels produce and compare that value to the max input voltage specification of your Deye?

 

[Joehebbo]

So what does the math tell you?
Here is a clue:
Calculate how many volts will 8 panels produce and compare that value to the max input voltage specification of your Deye?

Yeah that s what i am doing but the point here is i shouldn't reach 500 v i should stay under it for safety right? i can go 9 x 49.6 v Voc par panel 446 volt still under 500 volt the input voltage but i have the MPPT input should be under 425 so i have to go back to 8 x 49.6 =396 V

 

[LydMekk]

Panels are 545w longi with 40 v each direction south 29C beirut lebanon

Can't be right. I myself got Longi 540W 72 panels type 5 HiMo and they have 49 something volts STC...
ALWAYS use the STC number.
So, still - 8 in series per string. Max.

 

[Joehebbo]

Can't be right. I myself got Longi 540W 72 panels type 5 HiMo and they have 49 something volts STC...
ALWAYS use the STC number.
So, still - 8 in series per string. Max.

Yeah 49.6 my fault

 

[Joehebbo]

Can't be right. I myself got Longi 540W 72 panels type 5 HiMo and they have 49 something volts STC...
ALWAYS use the STC number.
So, still - 8 in series per string. Max.

Isc max is 28 Ad + 28 Ad not mentioned any voltage