SIRIUS 3RT1016-1KB42 — 24 VDC Power Contactor, Size S00
The Siemens 3RT1016-1KB42 is a SIRIUS power contactor in the Size S00 frame, designed for switching motor loads and resistive circuits in industrial control panels. Its 24 V DC coil draws 2.3 W for both closing and holding, so the power supply sizing is straightforward — no inrush spike beyond the steady-state draw. The contactor carries a 10 A rated operational current in AC-12 duty (resistive loads) and supports motor switching up to 4.5 kW at 500 V or 5.5 kW at 690 V. Mounting is screw and snap-on onto 35 mm DIN rail per EN 50022, with a 45 mm width that fits standard panel layouts. The screw-type terminals accept up to 4 mm² stranded or solid conductors, and the IP20 finger-safe enclosure protects maintenance staff during live troubleshooting.
Ratings and what they mean for your circuit
The AC-3 motor rating (not explicitly listed but inferred from the AC-2 and AC-4 values) governs the contactor's ability to switch squirrel-cage motors under normal starting conditions. The AC-2 rating of 4 kW at 400 V covers slip-ring motor starting, while the AC-4 rating of 8.5 A at 400 V applies to reversing or inching duty where the contactor makes and breaks stalled rotor current. For a buyer specifying motor starters, the AC-4 figure is the one that limits the contactor's life under heavy cycling — 30 million mechanical operations typical, but electrical endurance will be lower under AC-4. Short-circuit coordination is defined for both Type 1 and Type 2. With Type 2 coordination (minimal damage to the contactor after a fault), a gL/gG fuse of 20 A is required. For Type 1 coordination (contactor may need replacement after a fault), a 35 A fuse is acceptable. The pollution degree 3 rating means the contactor is suitable for industrial environments with conductive pollution, typical of most factory-floor panels. The integrated varistor surge suppressor clamps voltage spikes from the coil circuit, protecting the DC supply and nearby electronics. This is a factory-fitted option on the -1KB42 variant, so no external suppression module is needed — a time-saver during panel build.
Panel integration notes
The 72 mm depth leaves clearance behind the DIN rail for wiring — allow at least 100 mm from the backplane for finger access to the screw terminals. Side-by-side mounting is permitted with zero spacing. Operating temperature range of -25 to +60 °C covers most indoor panel environments.