SIRIUS power contactor, size S00 — 24 V DC coil, spring-loaded terminals
The Siemens 3RT1016-2DB44 is a SIRIUS power contactor in the compact size S00 frame, built for switching motor and resistive loads in control panels. Its 24 V DC coil draws 3.3 W for both closing and holding, so the control transformer or DC supply needs to be sized for that steady-state draw — no inrush peak to worry about with a DC coil. The main circuit uses spring-loaded terminals accepting 2x (0.25 to 2.5 mm²) solid or stranded, which speeds panel wiring compared to screw terminals. Rated for switching at 24 V DC up to 10 A, and at 400 V AC in AC-2 duty up to 4 kW. The AC-4 rating at 400 V is 8.5 A, which covers frequent inching or plugging duty on smaller motors. The varistor surge suppressor is built into the coil circuit, so no external snubber is needed for inductive load switching. Mounts via screw or snap-on onto a 35 mm standard mounting rail per DIN EN 50022. At 45 mm wide, it fits tightly on the rail — side-by-side mounting is permitted with 6 mm spacing to adjacent devices. IP20 on the front and terminals means finger-safe for panel installation, but not for washdown environments.
DIN-rail integration and panel fit
At 45 mm wide by 60 mm high by 114 mm deep, the S00 frame fits standard 35 mm DIN rail. The 114 mm depth is the dimension to check against enclosure depth and gland-plate clearance — it's the dimension that determines whether the contactor clears the back panel or door-mounted components. Side-by-side mounting is allowed with 6 mm air gap, so for a multi-contactor group you can pack them tight on the rail. Operating temperature range is -25 to +60 °C, with pollution degree 3 — suitable for the typical industrial control panel environment where conductive dust or humidity is present. The 2000 m maximum operating altitude covers most installations outside high-altitude mining or mountain sites.
Coordination and protection
For type 1 coordination (no damage to the contactor after a short circuit, but it may need replacement), the required upstream fuse is gL/gG 35 A. For type 2 coordination (contactor remains operational after a fault), the fuse is gL/gG 20 A. These are the values to pass to the panel designer for the short-circuit protection scheme. The contactor carries 2 instantaneous auxiliary contacts — these are the N.O./N.C. sets for feedback or interlocking. The auxiliary contact ratings at various voltages are listed: 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, 3 A at 400 V (–). The mechanical endurance is rated at 30,000,000 operating cycles, which is typical for the S00 frame in light-duty switching.