What it is and what it does
The Siemens SIRIUS 3RH1344-2CB00-0KA0-ZW97 is an auxiliary contactor in the size S00 frame, designed for switching control and signaling circuits in industrial panels. It carries four normally open (4 NO) instantaneous contacts, with no delayed, lagging, or make-before-break switching — a straight four-pole NO block for straightforward interlocking or PLC output extension. The coil is rated 24 V at both 50 Hz and 60 Hz, with a tolerance range of 0.8...1.1 × rated voltage at 50 Hz and 0.85...1.1 at 60 Hz, so it holds in across a typical control supply sag. A built-in varistor surge suppressor handles coil transients — no external snubber needed for standard PLC or relay driver outputs. Switching capacity covers a wide voltage range: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 1 A at 690 V AC, so it handles everything from low-voltage DC interposing relays up to 690 V motor control circuit isolation. The contact reliability spec — one incorrect switching operation per 100 million at 17 V, 1 mA — means it is trustworthy for dry-contact PLC inputs where low-energy switching is critical.
Mounting and integration
Mounts via screw or snap-on to DIN rail — the 45 mm width fits the standard S00 footprint, and the 114 mm depth leaves room for wiring. The mounting position is flexible: ±180° rotation on a vertical surface, plus ±22.5° tilt forward/backward. Terminals accept solid or stranded wire from 0.25 to 2.5 mm² (2 × conductors per clamp), which covers common control wiring sizes. IP20 on the front means finger-safe for panel installation; pollution degree 3 suits industrial environments with conductive dust or occasional condensation. Operating temperature range is -25 to +60 °C, with storage down to -55 °C and transport to +80 °C — fine for unheated warehouses or shipping in summer. Shock resistance is 10g at 5 ms and 5g at 10 ms, adequate for most machine-mounted panels.