Square D DU221RB 30A 240VAC 2-Pole Unfused Safety Disconnect

On the DC side, the National Electric Code (NEC), section 690.15, requires solar PV arrays to have a disconnecting means in order to isolate the grid-tie inverter from the photovoltaic power source. The DC disconnect utilized to perform this function must be rated at 600VDC. All Square D 600VDC are UL certified and rated NEMA 3R for outdoor use, allowing to mount the DC safety switch close to the solar array or in any other location where is required. They are available in 3-Pole 30A and 60A combined rating. There are fused and unfused versions of the 600VDC safety disconnect. The same disconnect can be used for 3 solar PV arrays. The wiring lugs can accommodate gauge 10-14 wire. The fused 600VDC safety disconnect can be customized to function as a combiner box. The non-fused 600VDC safety disconnect is rated to disconnect individual strings at full rated capacity.

On the AC side of the solar system, the utility company may require an AC safety disconnect between the grid-tie inverter and the electric load center. The AC safety switch is commonly mounted close to the grid service entrance to the building and is required to have a visible and lockable handle. All Square D 240VAC safety disconnects meet code requirements, they are UL certified and rated NEMA 3R for outdoor use. They are available in 2-pole and 3-pole format with 30A, 60A and 100A ratings; the AC disconnect needs to be sized for the full possible output of the grid-tie inverter.

Fuses are not included. Use Class-R fuses for fused disconnects.

Complete list of Square D safety disconnects for photovoltaic systems: