What it is and where it fits
The Siemens 3RH1344-1BF40 is a SIRIUS auxiliary contactor with a 110 V DC coil and 4 NO instantaneous contacts. Its size S00 footprint is 45 mm wide, 57.5 mm tall, and 111 mm deep.
What the ratings mean for the buyer
The 110 V DC coil draws a closing and holding power of 3.2 W — a steady-state load the control transformer or DC supply must cover. The 4 NO contacts are rated for utilization categories typical of auxiliary contactors: the 10 A at 24 V covers DC control loads; the 6 A at 230 V and 3 A at 400 V cover AC signal switching. The pollution degree 3 rating means it tolerates conductive dust in industrial enclosures. Surge voltage resistance of 6 kV gives adequate insulation coordination for 400 V panels. Contact reliability is specified as one incorrect switching operation per 100 million operations at 17 V, 1 mA — important for PLC-level dry circuits.
Panel integration notes
The size S00 body snaps onto a DIN rail or screws to a mounting plate. Mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward.