Siemens 3RT2015-1UB42 — SIRIUS Coupling Contactor, 24 V DC Coil, Size S00
The Siemens 3RT2015-1UB42 is a SIRIUS coupling contactor in size S00, designed for switching loads in control panels where a 24 V DC coil is specified. It mounts on 35 mm DIN rail per DIN EN 60715 via screw or snap-on fastening, and its 45 mm width fits standard panel layouts. The screw-type terminals accept solid or stranded conductors from 0.5 to 4 mm², including dual-wire terminations up to 2x 2.5 mm². The 24 V DC coil operates across a range of 0.8 to 1.1 times the rated value, meaning it picks up reliably at 19.2 V and holds in until dropout below about 18 V. The arcing time runs 10 to 15 ms, and the DC dropout delay is 7 to 13 ms — relevant when sequencing contactors in a safety circuit or interlock chain. Rated operational current at 400 V AC is 3 A, with a 0.75 hp rating at 230 V. The contactor is rated for 1,000 operations per hour at AC-1 (resistive loads), 750 at AC-3 (motor starting), and 250 at AC-4 (plugging/inching). Mechanical life is 30 million operations typical.
Mounting and Clearance
The 3RT2015-1UB42 requires 10 mm clearance above and below, 6 mm at the sides for airflow and arc containment. Depth is 73 mm, height 58 mm. Mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward — flexible for tight enclosures.