EATON Cutler-Hammer Series Safety Switch, Heavy Duty Fusible Single Throw, Series: DH Series, 600 VAC, 30 A, 10 hp, 20 hp, 1/3 ph, 3 Pole, 3 Wires, TPST, Class H Insulation, NEMA 3R, Panel Mount, 16-1/2 in L x 9-1/2 in W x 8-1/2 in H, Steel, Galvanized/Painted. NEC®, Article 210.63 requires that a 125 V, 1 ph, 15 A or 20 A rated receptacle outlet be installed at an accessible location for the servicing of heating, air-conditioning and refrigeration equipment. The receptacle must be located on the same level and within 25 ft of the heating, air-conditioning and refrigeration equipment.heavy duty safety switch is an ideal solution for these applications, including elimination of the need for running a separate 120 V circuit to the rooftop.