Reversing contactor assembly for motor reversing
The 3RA2318-8XB30-2BW4 is a Siemens SIRIUS reversing contactor assembly — a factory-wired pair of contactors with mechanical interlock, ready to reverse a three-phase motor without external interlocks. It ships with two 3RT2018-2BW42 contactors and the 3RA2913-2AA2 reversing kit already assembled, so the interlock timing and mechanical anti-overlap are set at the factory.
Motor power ratings and duty cycle
At 480 V the assembly carries 14 A continuous; at 600 V it carries 11 A — the current ceiling drops as voltage rises, which is typical for contactor thermal limits.
Mounting and panel integration
Clearance around the assembly: 6 mm upward, forward, downward, and to the side; 0 mm backward.
Termination and wiring
Auxiliary and control circuits also use spring-loaded terminals, consistent with the main circuit — one tool type for the whole assembly. AWG range for main contacts is 1x (20... 12), covering typical motor feeder sizes in that power class.
Environmental and compliance
Shock resistance rated 11.4 g / 5 ms and 7.3 g / 10 ms for both AC and DC axes.