Size S00 power contactor, 24 V DC – panel-ready
This is a Siemens SIRIUS 3RT1016-1BB41 power contactor, Size S00, meaning it fits the smallest frame in the line – 45 mm wide, 57.5 mm tall, 72 mm deep. Coil pulls in at 24 V DC, holds at 3.3 W. Auxiliary contacts switch 10 A at 24 V DC, rated AC-12 for resistive loads. Screw terminals on both main and control circuits. Mounts via screw or snap-on onto 35 mm DIN rail per EN 50022.
Not a drop-in for the 3RT2028 frame
If your BOM originally specified a 3RT2028-1BB40, this 3RT1016-1BB41 is a different frame size – S00 versus S0 (or S2). The mounting footprint, terminal spacing, and current ratings diverge enough that you can't swap without panel rework. The 3RT2028 family handles higher motor currents; the S00 is for smaller loads up to about 5.5 kW at 690 V. Stick with the correct frame for the job, but if you're sorting a mixed lot, this one moves fast for low-power switching.
Terminal and wiring details
Screw terminals accept solid or stranded wire: 2x (0.5–1.5 mm²), 2x (0.75–2.5 mm²), up to 2x (0.75–4 mm²) for main contacts. For AWG, that's 2x 20–16, 2x 18–14, 1x 12. Auxiliary contacts take the same gauge. Pollution degree 3, IP20 on front and terminals. Side-by-side mounting permitted, no derating gap needed.