1100V Max DC Input

[CarlSEL]

Hi,

The Sungrow 150k Inverter states a maximum DC Input of 1100V. When using DMEGC 510W PV mods we have been given string lengths of 24 by PVSol on our reports.

Sungrow have now told us that the maximum length of PV mods for this invert is actually 22 modules at -10 degrees.

The Voc of the modules at -10 degrees is 44.45V. so 44.45 x 24 = 1066.8V

Is this getting through to the report due to Sungrow inputting the incorrect Max DC V?

Thanks

[hotline_oh]

Dear CarlSEL,

Thank you for your inquiry.

We confirm that the manufacturer Sungrow has listed the SG150CX inverter with a maximum input voltage of 1100 V in our database:

According to the datasheet, the open-circuit voltage of the DM510M10RT-B60HSW/HBB/HBW/HBT/HST module under STC conditions (25 °C) is 45.1 V.

The maximum open-circuit voltage is calculated for -10 °C. The temperature coefficient of the voltage is -0.247%/K or -111.5 mV/K. The temperature difference from +25 °C to -10 °C is 35 Kelvin. This temperature difference leads to a voltage increase of 35 K * 0.1115 V/K = 3.90 V. This results in a maximum open-circuit voltage of 45.1 V + 35 K * 0.1115 V/K = 49.0 V per module.

String with 21 modules: 1029.05 V
String with 22 modules: 1078.06 V
String with 23 modules: 1127.06 V
String with 24 modules: 1176.06 V

PV*SOL allows the connection of 21 modules (normal range) or 22 modules (MPP voltage tolerance range of 865.7 V, normal open-circuit voltage range of 1078.1 V).

We cannot reproduce your configuration with 24 modules. Please send us a screenshot or the project file (*.pvprj) to hotline@valentin-software.com, and we'll take a look at it.