Q: We are often asked “How many panels can I have in relation to an inverter size?”

A: There is a limit to how many PV panels can be connected to a string inverter. Not all inverters are crated equal in what DC input capacity they can handle. Also, the number of strings comes into play.

For the sake of this exercise, lets assume a system with 1 string to a central 3kw string inverter.

Whereas some specs relate to wattage, the more accurate measure is the total voltage the panels supply to the inverter.

Lets look at a typical 3 kw inverter.

Max DC input power (to the inverter) 600v (volts)

If we were to install the Trina 235 w Honey Black module (panel) which has an open circuit voltage of 40.4, we could connect 14 panels

Total voltage = Voltage (V) ea panel  x No of panels = max voltage to inverter.

In this case

40.4 x 14 = 565v.

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