What it is and where it fits
The Siemens 3RT1016-1BA42 is a SIRIUS-brand power contactor in the Size S00 frame, designed for switching motor loads and resistive loads in control panels. It mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 50022, so it integrates directly into a standard panel layout without adapters. Rated for AC-12 duty at 10 A maximum, this contactor handles resistive and lightly inductive loads in control circuits. For motor switching, it carries 4.5 kW at 400 V (AC-2) and 5.5 kW at 690 V, covering common three-phase induction motors in that power band.
Key ratings and what they mean for fit
The AC-12 rating of 10 A tells you this contactor is suited for switching resistive loads like heaters or lamp banks in control circuits — not for heavy motor inrush. For motor duty, look at the AC-2 rating (4 kW at 400 V) which covers slip-ring motors, or the AC-4 rating (8.5 A at 400 V) for reversing or plugging duty. The 4.5 kW at 400 V and 5.5 kW at 690 V ratings are the practical motor sizing numbers for standard induction motors. DC switching capability is specified across voltages: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V. That covers DC coil circuits and small DC load switching in mixed-voltage panels. The magnet coil draws 3.3 W both during closing and holding — a DC-operated coil that doesn't spike on pickup, which simplifies the power supply sizing in the panel. Type 2 coordination requires a 20 A gL/gG fuse; Type 1 allows a 35 A fuse. That's the short-circuit protection the upstream breaker or fuse must provide to keep the contactor from welding on a fault.
Physical integration
The 45 mm width and 57.5 mm height fit the Size S00 footprint — compact enough for dense DIN-rail layouts. Depth is 72 mm, which clears most standard enclosure depths. Side-by-side mounting is permitted with a 6 mm spacing to adjacent devices. Screw-type terminals on the main circuit accept 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or up to 2x (0.75 to 4 mm²) — covering standard control wiring. AWG equivalents are 2x (20 to 16), 2x (18 to 14), and 1x 12. Front and terminal protection is IP20, meaning finger-safe but not washdown-rated. Operating temperature range is -25 to +60 °C, with a maximum altitude of 2,000 m. Pollution degree 3 means it's rated for industrial environments with conductive pollution — typical for an unsealed panel.