SIRIUS S00 Power Contactor with Spring-Terminal Coil Connection
The Siemens 3RT2018-2CP04-3MA0 is a SIRIUS-branded power contactor in the compact S00 frame size, designed for switching motor loads and resistive circuits in industrial control panels. Its defining feature for this order code is the spring-type terminal on the magnet coil, which eliminates the need for screwdriver torque verification on the coil connection — a time-saver during panel wiring and a reliability point in high-vibration environments. The contactor mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, fitting the standard panel layout without adapter plates. The S00 footprint is 45 mm wide, 70 mm tall, and 121 mm deep. Mounting position allows +/-180° rotation on a vertical surface and +/-22.5° tilt forward/backward.
Switching Frequency and Duty-Cycle Limits
Maximum switching rates are specified per AC duty class: 1,000 operations per hour at AC-1 (resistive load), 750/h at AC-2 and AC-3 (slip-ring and squirrel-cage motors), and 250/h at AC-4 (plugging/reversing). The AC-3e rating also caps at 750/h. For a conveyor or pump running at 30 starts per hour, these limits are generous; for a rapid-reversing application like a crane hoist, the AC-4 ceiling of 250/h is the binding constraint — exceeding it risks contact welding and reduced mechanical life.
Auxiliary Contact Ratings and Wiring Details
The contactor carries no built-in auxiliary switch block, so any auxiliary contacts must be added as separate side-mounted units. When present, the contact ratings span the control-voltage range: 6 A at 24 V, 2 A at 48 V and 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, and 3 A at 400 V. The 440 V rating drops to 0.2 A. These are the make/break capacities for the auxiliary circuit — useful for sizing PLC inputs or relay coils downstream. Wire sizes accepted: solid or stranded 0.5 to 4 mm², with dual-wire capability up to 2x (0.5 to 4 mm²) per terminal. Clearance around the contactor: 10 mm upward and forward, 10 mm downward, 6 mm at the side — tight enough for dense panel layouts but leaves room for finger-safe shrouding.