The Siemens 3RT1346-1BD40 is a SIRIUS S3 power contactor — screw-type main and auxiliary terminals, rated for switching motor loads up to 53 kW at 230 V (AC-3 duty) and carrying an insulation voltage of 1 000 V. It mounts on 35 mm or 75 mm standard DIN rail via screw and snap-on fastening, with side-by-side mounting permitted — no gap required between units on the rail. Operating temperature range is -25 to +60 °C, storage -55 to +80 °C, with pollution degree 3 (conductive pollution typical in industrial enclosures).
RoHS compliance date is 05/01/2012 per the substance prohibitance entry.
Main circuit terminals accept solid conductors: 2x (0.5–1.5 mm²), 2x (0.75–2.5 mm²), max 2x (0.75–4 mm²). Stranded: 2x (10–50 mm²). For AWG: 2x (10–1/0). At 40 °C minimum permissible is 50 mm²; at 60 °C derate to 35 mm². Auxiliary and control circuits also use screw-type terminals; the magnet coil closing power at DC is 15 W.
Protection and coordination
Enclosure protection: IP20 on the front with cover or box terminal; the terminal itself is IP00 — so panel builders need to account for that in the gland plate and fill factor.