What it is and where it fits
The Siemens 3RT2016-1AQ02 is a SIRIUS power contactor in Size S00 — the smallest frame in the SIRIUS family, built for panel density. It mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, and the mounting position is flexible: you can rotate it ±180° on a vertical surface or tilt it forward/backward ±22.5°, which helps when you're squeezing it into a crowded enclosure and the rail isn't perfectly level. The coil is 24 VDC with screw-type terminals, so it's a straightforward install — no special tooling needed at the panel. The contactor carries an auxiliary switch, which gives you a feedback signal for the PLC or a status light without adding a separate block.
Rated for the real duty cycle
The switching frequency tells you what this contactor is built for: up to 750 cycles per hour in AC-3 duty (standard motor starting), and 250 cycles per hour in AC-4 (plugging or inching). That AC-3 rate covers most conveyor, pump, and fan applications. The AC-1 resistive load rate is 1,000 cycles per hour, which is fine for heater banks or lighting contactor duty. Mechanical life is typical at 30 million operations, so this is a set-and-forget part for most panel builds. The contactor's arcing time runs 10 to 15 ms at 50/60 Hz, which is within the normal range for this frame size — no surprise for a Size S00 block.
Wiring and clearances
Terminals accept solid or stranded wire from 0.5 to 4 mm², and you can land two conductors per clamp — 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or 2x 4 mm². That's useful for daisy-chaining control power or paralleling outputs without a separate terminal block. Clearance around the contactor is tight: 10 mm upwards, 10 mm forwards, 10 mm downwards, and 6 mm at the sides. That 6 mm side gap is the one to watch — if you're packing multiple contactors side by side, maintain that air gap for heat dissipation and arc flash clearance. The overall dimensions are 45 mm wide, 58 mm high, and 73 mm deep, which is a compact footprint for a 24 VDC motor contactor.
Lifecycle and sourcing
The operating temperature range is -25 to +60 °C during operation, with storage from -55 to +80 °C. That covers most indoor panel environments and even unheated warehouses. For compliance, the SIRIUS line typically carries UL, CSA, and CE markings, though the specific approvals for this order code should be confirmed at quote time against your jurisdiction's requirements.