Siemens 3RT1336-1AT60 SIRIUS Power Contactor — S2 Frame, 11 kW AC-2 Motor Duty
The Siemens 3RT1336-1AT60 is a SIRIUS power contactor in the S2 frame size, designed for switching motor loads in industrial control panels. Its headline rating is 11 kW at AC-2 duty at 400 V — that's the category for slip-ring motor starting and reversing, where the contactor makes and breaks the rotor current under load. The 690 V rated insulation voltage gives headroom for 400 V line-to-line systems with grounded wye configurations, and the pollution degree 3 rating means it's suited for industrial environments with conductive dust or condensation — no derating for dirty air in a typical panel. Mounting is screw and snap-on onto 35 mm DIN rail per EN 50022. The front face carries IP20 protection — safe for finger contact in an open panel — while the terminal area is IP00, meaning live parts are exposed at the wiring point. Side-by-side mounting is permitted, so you can gang multiple contactors on the same rail without a mandatory gap, though the thermal derating curve should be checked for full-load continuous duty above 40 °C ambient.
Termination and Wiring — Screw-Type Main and Auxiliary Circuits
Both the main current circuit and the auxiliary/control circuit use screw-type terminals. The main circuit accepts solid conductors from 2x (0.5... 1.5 mm²) up to max 2x (0.75... 4 mm²), and stranded conductors from 2x (0.75... 25 mm²). For the control circuit, solid or stranded 2x (0.75... 16 mm²). AWG equivalents for the main contacts are 2x (18... 2). The minimum permissible cross-section at both 40 °C and 60 °C is 16 mm² — that's the smallest wire that can carry the rated current without exceeding the terminal temperature rise. The protection recommendation for type of assignment 2 (coordination with short-circuit protective device) is a gL/gG fuse rated 63 A. That's the fuse size that limits let-through energy to protect the contactor during a bolted fault. For a panel builder, this means the upstream fuse holder or MCCB branch must be sized to accommodate a 63 A fuse — not a smaller general-purpose breaker.
Duty Ratings and Switching Performance
Beyond the AC-2 motor rating, the contactor carries specific switching capacities for auxiliary contacts at various voltages: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, 0.3 A at 220 V, 6 A at 230 V, and 3 A at 400 V (–). These are the make/break ratings for the auxiliary contact block — useful for interlocking, status feedback, or PLC input circuits. The arcing time is 10 to 15 ms, and the mechanical life is typical 10,000,000 operations. At AC-1 maximum (resistive load), the switching rate is 1,000 cycles per hour. The coil operates across a voltage range of 0.8 to 1.1 times the rated control supply voltage at 60 Hz, with a pick-up time of 10 to 30 ms at AC. The rated control supply voltage at 60 Hz is 600 V — that's the coil voltage, not the main circuit. For a 24 VDC coil variant, the 10 A rating at 24 V applies to the auxiliary contacts, not the coil itself.