What It Is and Where It Lands
The Siemens 3RT1023-1AN60 is a SIRIUS power contactor in the S0 frame size, designed for switching motor loads in industrial control panels. It mounts via screw or snap-on onto 35 mm standard mounting rail per DIN EN 50022, so it integrates directly into a standard DIN-rail enclosure without adapter plates. Rated for AC-2 duty at 4 kW and AC-4 at 8.5 A, both at 400 V, this contactor handles reversing, plugging, and inching applications where the motor is switched under load. The AC-4 rating is the one that governs real-world wear on the contacts — the 8.5 A figure tells you the maximum repetitive switching current for those demanding cycles.
Key Ratings and What They Mean for Fit
Motor power ratings: 4.5 kW at 500 V and 5.5 kW at 690 V. These are the maximum three-phase induction motor loads the contactor can switch in AC-3 duty. If your motor nameplate falls within these, the 3RT1023-1AN60 is sized correctly for continuous switching. The auxiliary contact block carries 10 A at 24 V, 6 A at 230 V, and 0.3 A at 220 V DC. The DC ratings drop sharply with voltage — at 220 V DC the 0.3 A limit is the one to watch for inductive loads like relay coils or small DC solenoids. Operating temperature range of -25 to +60 °C, with pollution degree 3 (conductive pollution or dry non-conductive pollution that becomes conductive due to condensation). This means it's suited for typical industrial environments but not for clean rooms or sealed enclosures without condensation management. Maximum operating altitude of 2 000 m. Above that, dielectric strength and cooling derate — if your installation is at elevation, factor that in.
Wiring and Termination
Main current circuit uses screw-type terminals. Accepts solid conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), max 2x (0.75 to 4 mm²). For stranded: 2x (1 to 2.5 mm²), 2x (2.5 to 6 mm²), max 2x 10 mm². AWG equivalents: 2x (16 to 12), 2x (14 to 10), 1x 8. This covers most panel wiring from signal-level to moderate power feeds. Short-circuit protection coordination: Type 1 requires a gL/gG fuse rated 63 A; Type 2 requires 25 A. The Type 2 coordination limits fault energy to prevent contact welding, so if your panel design specifies Type 2, use the 25 A fuse.
Lifecycle and Sourcing Reality
Mechanical endurance is rated at 10 million operating cycles typical. That's the mechanical life of the contactor assembly — electrical life will be lower depending on the switching load and duty cycle.
Physical Fit and Panel Integration
Dimensions: 85 mm height, 45 mm width, 91 mm depth. The S0 frame is one of the compact sizes in the SIRIUS family — 45 mm wide means it occupies a single 45 mm slot on the DIN rail, leaving room for aux contact blocks or other devices in the row. Side-by-side mounting is permitted (zero spacing between units), which saves rail space in dense panels. Front protection is IP20 (finger-safe), while the terminal area is IP00 (open terminals) — so the panel enclosure provides the overall ingress protection. Rated control supply voltage: 200 V at 50 Hz, 200 to 220 V at 60 Hz. The coil operates across 0.8 to 1.1 times the rated voltage at 50 Hz, and 0.85 to 1.1 at 60 Hz. This means the coil holds in reliably even if the control supply sags 20% at 50 Hz or 15% at 60 Hz.