What it is and what it does
The Siemens 3RT1016-2BW44 is a SIRIUS 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, making it a standard drop-in for European-pattern panels. The DC coil is rated 24 V nominal with a pickup threshold of 0.85 x rated value (20.4 V) and a dropout below that. Closing and holding power is 3.3 W DC — steady-state draw is low enough that a standard 24 VDC power supply can drive multiple contactors without derating. Main contacts are spring-loaded terminals accepting 2x (0.25 to 2.5 mm²) solid or stranded, or 2x (24 to 14 AWG). The IP20 finger-safe terminal shroud means the panel builder doesn't need additional touch protection at the contactor — it's safe for live work with a screwdriver, not fingers.
Switching ratings — what they mean for your load
For DC switching, the contactor is rated 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V. These are resistive-load figures; inductive DC loads (relays, solenoids) need a flyback diode across the load or the contacts will arc on opening. The 10 A at 24 VDC covers most solenoid valve banks and small DC motor brakes. On AC motor duty, the contactor delivers 6 A at 230 V (approx. 1.5 kW), 3 A at 400 V (4 kW in AC-2, 8.5 A in AC-4), and 5.5 kW at 690 V. The AC-4 rating of 8.5 A at 400 V is the one to watch for reversing or plugging duty — it's lower than the AC-3 thermal current because of the higher switching frequency and arcing stress. Short-circuit coordination: with type 2 coordination (no damage to the contactor), use a gL/gG fuse rated 20 A. For type 1 (contactor may need replacement after fault), a 35 A fuse is acceptable. The SCCR depends on the upstream breaker — the contactor itself doesn't limit fault current.
Lifecycle and sourcing
For a BOM freeze or line-down replacement, this is a direct drop-in for any panel designed around a Size S00 contactor with a 24 VDC coil and spring-clamp terminals. The 45 mm width and 114 mm depth fit standard DIN-rail spacing with 6 mm side clearance to adjacent devices.
Where it fits — panel integration
Mounts on 35 mm DIN rail per EN 50022. Side-by-side mounting is allowed (no derating required for adjacent contactors at rated current up to 60 °C ambient). The 45 mm width matches the S00 footprint — three units fit in a 145 mm wide enclosure section. Operating temperature range is -25 to +60 °C, with a maximum altitude of 2 000 m without derating. Pollution degree 3 means it's suited for industrial environments with conductive dust or humidity — not for clean rooms or sealed enclosures without filtration. The spring-loaded terminals accept 0.25 to 2.5 mm² (24 to 14 AWG). Strip length is typically 8-10 mm for spring-cage terminations. No special tools needed beyond a screwdriver to push the orange release button.
Compliance and documentation
The reference code per DIN EN 81346-2 is Q (power switching device). This contactor carries CE marking for the European market and is designed to meet IEC 60947-4-1 for contactors and motor-starters. RoHS and REACH compliance documentation is available from Siemens upon request.