Is it ok to put two grid tie inverters on same Ac line two main panel

jdroof

As Title asks is it ok to combine two Ac lines from grid tie inverters in to one to main disconnect then to breaker panel.

Thanks

BB.

Assuming you are in the US (NEC--New Jersey?), need to ask about the ratings of your two GT inverters.

A circuit breaker (fuse) protects the wiring from the main panel to the load. A 15 Amp breaker uses 14 AWG wiring, a 20 amp breaker uses 12 AWG wiring, etc. (per NEC code--plus other deratings possible).

So--If you have two "small" inverters (say 1 amp each micro inverters ~240 Watts @ 240 VAC rating)--Then you can put upwards of 17 of them on a 20 Amp @ 240 VAC circuit.

If you have a pair of 3 kWatt inverters:

• 3,000 Watts * 1/240 VAC * 1.25 NEC derating = 15.6 Amps ~ 20 Amp minimum branch circuit (breaker+12 awg wiring)

If you where to put two GT inverters on a single branch circuit, then the circuit would need to be rated at 40 Amps (next largest standard breaker) with wiring to support 40 amp branch circuit.

You then need to look at the manual for the GT inverter and see what is the Maximum Branch Circuit rating (and AWG cable size) it supports.

If the inverters can support a 40 amp circuit, then you can wire a single circuit to both GT inverters. If they cannot, then you would need a separate 20 amp branch circuit to each.

Otherwise, you next option would be to add a sub panel with (as an example) 40 amp feed and 2x 20 amp branch breakers. You would need to check with your building department... They have rules on how to use sub panels with GT inverters (typically, the sub panel must be labeled "For Solar Circuits Only, No Other Loads Allowed" or something similar).

Make sense?

-Bill

jdroof

Thanks