What it is and what it does
The Siemens 3RT1017-1BB41-ZW98 is a SIRIUS power contactor in size S00, rated for switching motor loads up to 5.5 kW at 400 V AC (AC-3 duty) and 5.5 kW at 690 V. The 24 VDC coil draws 3.3 W holding power, with a pick-up threshold of 0.85 x rated voltage (20.4 V) and a drop-out of 0.1 x rated voltage (2.4 V), so it stays latched through typical supply dips but releases cleanly on undervoltage. For heavy-duty reversing or inching (AC-4), it carries 8.5 A at 400 V — a useful spec for conveyor or hoist applications where frequent starts under load are the norm. The DC switching capability at 24 V is 10 A, covering solenoid and small DC motor loads.
Mounting and integration
Mounts via screw or snap-on onto a 35 mm DIN rail per EN 50022. The 45 mm width and 72 mm depth leave room for side-by-side mounting without derating, making it a dense fit in a standard panel enclosure. Screw-type terminals on the main circuit accept solid or stranded conductors up to 4 mm² (AWG 12) — double up to 2.5 mm² per clamp for paralleled feeds. IP20 finger-safe protection on the front and terminals means it's safe for open-panel installation behind a locked door, but not for washdown zones.
Coordination and protection
For type 1 coordination (no weld prevention, just no fire risk), use a 35 A gL/gG fuse upstream. For type 2 coordination (contactor remains operable after a fault), drop to a 20 A gL/gG fuse. This is the spec the panel designer needs to match the short-circuit rating of the MCC. Operating temperature range of -25 to +60 °C covers most indoor industrial environments; altitude limit is 2000 m without derating.