Hello,

My name is Ahmad Elghobashy from Egypt

I do have a question and don't know what to do , and I think maybe you can help

I have a string of 20 modules of Jinko solar panels JKM 310Wp

now from the data sheet the open circuit voltage is 45.9 V

So the total string open circuit voltage is 918 V

now in the system check I get 1018 V

So the max. allowed open circuit is exceded

but I don't know why there is a 100 V over the stated in the data sheet

 

Best regards,

Ahmad Elghobashy

Egypt

Hello Mr. Elghobashy,

the open circuit voltage specified in the data sheet is only valid for STC conditions, ie 25 ° C module temperature. The lower the module temperature, the higher the open-circuit voltage is. For your module, this value is -142.29 mV / K. In our system check, we test the system under extreme conditions, that you can define yourself. The default is to calculate the maximum voltage at 1000 W / m² and -10 ° C. If you are planning mostly in Egypt, you should here rather enter 1100 W / m² and           + 5 ° C.  You can change these values on page „inverters“. Klick the link Configuration limits. On page Miscellaneous you can change the values.

Best regards,

Rainer Hunfeld