What it is and what it does
The Siemens 3RT1035-1AP04-ZX95 is a SIRIUS power contactor in size S2, rated for switching motor loads up to 22 kW at 500 V in AC-3 duty (the standard category for squirrel-cage motors during starting and running). Its AC-4 rating of 35 A at 400 V covers plugging and inching applications where the contactor makes and breaks stalled rotor current. The contactor mounts on a 35 mm DIN rail per EN 50022, using either screw fixing or snap-on — typical for panel integration where you need to swap a unit without removing adjacent devices. Dimensions are 55 mm wide, 112 mm high, 164 mm deep, fitting standard S2 footprint enclosures.
Lifecycle and compliance
The contactor carries a RoHS compliance date of 05/01/2012, confirming it meets the EU directive on hazardous substances. Pollution degree 3 rating means it's suitable for industrial environments with conductive pollution or dry non-conductive pollution that becomes conductive due to condensation.
Termination and wiring
Main circuit terminals are screw-type, accepting solid conductors from 2x (0.5... 1.5 mm²) up to 2x (0.75... 4 mm²) for the control circuit, and stranded conductors up to 2x (0.75... 25 mm²) for the power circuit. The minimum permissible cross-section at 40 °C is 16 mm², which sets the lower bound for thermal sizing.
Environmental and switching performance
Operating temperature range is -25 to +60 °C; storage range extends from -55 to +80 °C. The contactor is rated for 10 million mechanical operations typical, with switching frequencies up to 1 200 cycles per hour at AC-1, 1 000 at AC-3, and 300 at AC-4. Arcing time is 10 to 15 ms, and the contactor can be mounted side-by-side without derating.