Reversing contactor assembly for 3-phase motor reversing
The Siemens 3RA2335-8XB30-1AC2 is a factory-assembled reversing contactor assembly from the SIRIUS family, designed to reverse a three-phase motor by mechanically interlocking two contactors so only one can close at a time. It ships with two 3RT2035-1AG20 contactors already mounted and wired on a common base plate, saving panel-build time and eliminating the risk of incorrect interlock wiring. Rated at 18.5 kW at 400 V AC-3 (40 A at 480 V, 41 A at 600 V), it handles reversing duty on pumps, conveyors, and other three-phase induction motors up to that power class. The 24 V 50/60 Hz coil draws 0.36 A at 50 Hz and 0.39 A at 60 Hz, so the control transformer must be sized accordingly.
The S2 frame measures 141 mm high by 120 mm wide by 130 mm deep, leaving clearance of 10 mm upward, downward, and to the sides, and 0 mm backward — meaning it can sit flush against the panel back wall.
Main current circuit terminals are screw-type, accepting solid conductors from 1 to 35 mm² (two per pole) and up to 50 mm² for a single conductor. The magnet coil also uses screw terminals, with a separate set of terminals for the auxiliary contacts — two instantaneous contacts are built in.