ABB OS30FAJ12 Disconnect Switch Brand: ABB. Part Number: OS30FAJ12. ABB Disconnect Switch, Front Operated Fusible Open, Series: OS Series, 600 VAC, 30 A, 20 hp, 50/60 Hz, 3 Pole, Base Mount, Screw Terminal, 40 deg C, 100 mm H x 143 mm W x 119 mm D. Additional Description: ABB -OS30FAJ12 3P 30A J FUSIBLE SW. Catalog Description: Switch Fuses,Front operated,3-pole,12 (Between the Poles),Class J,30 A,Handle and shaft not included..