What it is and what it does
The Siemens 3RT2018-2XJ41-0LA2 is a SIRIUS contactor in the Size S00 frame, designed for switching loads in control panels. Its 72 VDC coil is terminated via spring-type terminals, which means no screwdriver is needed for the coil wiring — a time-saver during panel build-out and a reliable connection under vibration. The contactor carries an auxiliary switch block, giving you a set of N.O./N.C. contacts for status feedback or interlocking without adding a separate side-mount unit. The auxiliary contacts are rated at 10 A at 24 V and 14 A at 480 V, so they handle pilot duty and small motor loads directly.
Mounting and integration
Mounts via screw or snap-on onto a 35 mm DIN rail per EN 50022. The 45 mm width means it occupies one standard modular device slot. Clearance requirements are 10 mm upwards, 10 mm forwards, 10 mm downwards, and 6 mm to the side — tight enough for dense panel layouts. The mounting position is flexible: the contactor can be rotated ±180° on a vertical surface, tilted forward/backward ±22.5°, or mounted standing on a horizontal surface. This accommodates non-standard panel orientations or retrofit into existing enclosures.
Wiring and termination
Main contact and coil terminals accept solid or stranded conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or 2x 4 mm². The spring-type terminals on the coil side hold the wire without retightening — strip, insert, done.
Switching performance
The DC coil has a pick-up/drop-out time of 25 to 45 ms, and the main contacts have an arcing time of 10 to 15 ms. These figures matter for sequencing: if you're interlocking two contactors, the overlap window is defined by these timings.