Ratings and fit for motor loads
The 3RT2018-1UB42-1AA0 is a Size S00 power contactor rated AC-3e/AC-3 at 16 A, switching 7.5 kW at 400 V across three poles. The AC-3e rating means it is certified for switching squirrel-cage motors — making and breaking the motor's locked-rotor current during starting and stopping. The 16 A AC-3e figure is the duty-class rating that governs real motor load fit, not a generic thermal current. The coil is 24 V DC with an integrated varistor for suppression. The varistor clamps the inductive kick when the coil de-energizes, which protects nearby PLC outputs or relay contacts sharing the same DC supply rail. The auxiliary contact is 1 NC — one normally-closed feedback contact for status indication or interlocking.
Compliance documentation is available: RoHS compliant since October 1, 2009, and REACH Article 33 information is published on the current candidate list.
Upright mounting position is specified — horizontal or inverted mounting may require derating. Screw terminals accept standard power and control wiring; the integrated varistor is internal, so no external suppression module is needed on the coil circuit. Packaged singly, dimensions 63 x 80 x 50 mm. The 1 NC auxiliary is built in; additional auxiliary contact blocks can be front-mounted if more feedback signals are needed, but the base unit carries one NC as standard.