Hi! Can you clarify your question? Are you implying and asking why do lower capacity inverters (smaller inverters like residential) have higher fault current contribution than larger inverters (utility scale)? If so can you share two models as examples so that I better understand the question and see the type of inverter and fault current ratings on both models?
@@uptopsolar yes my question is, why low capacity of inverter has max fault current contribution (1 cycle RMS) is more than high capacity of inverter of max fault current contribution (1 cycle RMS) . For example:- a. Cps inverter model name CPS SCA 36ktl-DO/US- 480 has fault current contribution (1 cycle RMS) is 73.2A (1.68 PU), while b. Cps inverter model name CPS SCA 60 ktl-DO/US-480 has maximum fault current contribution (1 cycle RMS) 64.1 A (1.6/0.88 PU).
The max PV power of the string can be higher than specified for the DC input upto around 150%. The converter will "ignor" this extra available power and not convert it to the AC side. This will result on clipping the highest possible level, but this lost is only a few procents in regard to the total converted value. As a positive effect, the converter will convert power over a larger time span during a day, so produce more AC power. A second general mistake is that the each panel directly generated it's almost full voltage the moment some light shines on it, so the minimum MPPT voltage is directly exceeded. The string presents however a very low current at this low light level. The output current will be linear with the amount of light shining on the string. The converted will decide how much DC power is converted to AC power.
I couldn't find the SMA manual that shows this, but from my experience with other inverters... MPPT Operating Voltage Range is where the inverter can operate and perform some MPPT, it's a wider range. Then Rated MPP Voltage range is the range where the inverter can out put it's max power. So in this example it appears that between 100Vdc and 155Vdc there could be some derating, same thing on the high end (between 480Vdc and 550Vdc). Between 155Vdc and 480Vdc, you could expect full power output.
No, the voltage is immediately there the moment some light hits the string. The string generates however hardly any current as only a view number of atoms are hit by the light. Current generation will linear increase with the increase of light on the panel upto a maximum where the maximum output is reached. See an episode of Gerry does Solar.
You're good easy to understand or follow. Thanks
Thanks, I appreciate the kind words!
Could you explain....why max fault current contribution is greater in low capacity of solar inverter compare to high rating solar inverter.
Hi! Can you clarify your question? Are you implying and asking why do lower capacity inverters (smaller inverters like residential) have higher fault current contribution than larger inverters (utility scale)? If so can you share two models as examples so that I better understand the question and see the type of inverter and fault current ratings on both models?
@@uptopsolar yes my question is, why low capacity of inverter has max fault current contribution (1 cycle RMS) is more than high capacity of inverter of max fault current contribution (1 cycle RMS) .
For example:-
a. Cps inverter model name CPS SCA 36ktl-DO/US- 480 has fault current contribution (1 cycle RMS) is 73.2A (1.68 PU), while
b. Cps inverter model name CPS SCA 60 ktl-DO/US-480 has maximum fault current contribution (1 cycle RMS) 64.1 A (1.6/0.88 PU).
The max PV power of the string can be higher than specified for the DC input upto around 150%. The converter will "ignor" this extra available power and not convert it to the AC side. This will result on clipping the highest possible level, but this lost is only a few procents in regard to the total converted value. As a positive effect, the converter will convert power over a larger time span during a day, so produce more AC power.
A second general mistake is that the each panel directly generated it's almost full voltage the moment some light shines on it, so the minimum MPPT voltage is directly exceeded. The string presents however a very low current at this low light level. The output current will be linear with the amount of light shining on the string. The converted will decide how much DC power is converted to AC power.
Whats the difference between Rated MPPT Voltage range and MPPT Operating Voltage range?
I couldn't find the SMA manual that shows this, but from my experience with other inverters... MPPT Operating Voltage Range is where the inverter can operate and perform some MPPT, it's a wider range. Then Rated MPP Voltage range is the range where the inverter can out put it's max power. So in this example it appears that between 100Vdc and 155Vdc there could be some derating, same thing on the high end (between 480Vdc and 550Vdc). Between 155Vdc and 480Vdc, you could expect full power output.
@@uptopsolar Thanks for the information!
No, the voltage is immediately there the moment some light hits the string. The string generates however hardly any current as only a view number of atoms are hit by the light.
Current generation will linear increase with the increase of light on the panel upto a maximum where the maximum output is reached. See an episode of Gerry does Solar.
Makes no sense to me