Help please. Solar PV Max System Voltage Calc.

[Loffgren]

Looking for calc for solar pv max system voltage for a parallel circuit. ? I only see series circuit in code book.

I have a drawing for a customer that has the max system voltage at 42.9V for an 8 module parallel system

 

[SIRSPARKSALOT]

Would you provide more information:
What type of application?
Why is the system voltage only at 42.x volts?
Typically, panels are wired in series to build the necessary voltage necessary to start the inverter and then put together in parallel (combiner boxes) in order to build amperage.

 

[jaggedben]

Max system voltage for paralled strings (or panels) is the same as max system voltage for any single string (or panel) in the system. It is the sum of the open circuit voltages for all panels in a string, multiplied by an appropriate factor found in table 690.7. If all panels are connected individually in parallel, then each string is one panel.

42.9V is a plausible max system voltage if the 8 panels are indeed connected in parallel, although we would need more info to know if it is correct.

I would gather that this is an off-grid system or hybrid system (or else that the person who made the drawing does not know what they are doing). Grid-tied systems would not be configured this way.