Disconnect Boxes

The National Electric Code, section 690.15, PV requires arrays to have a disconnecting means to isolate the inverter from the PV power source. Utility grid-tie inverters that utilize PV arrays with voltages above 250VDC require a disconnect rated for 600VDC to perform this function. Most utilities also require an AC disconnect between a grid-tie inverter and the AC load center (close to the AC service entrance, with a visible/lockable handle). A 30A 240V disconnect is good for up to 5kW at 240VAC, the 60A is good for up to 11kW.