What it is and what it does
The Siemens 3RH1344-2CB00-0KA0-ZX95 is a SIRIUS auxiliary contactor in Size S00, designed to switch control circuits in motor starter and contactor assemblies. It carries 4 NO instantaneous contacts rated 10 A at 24 V, with a varistor built in for surge suppression across the coil. The 10 A rating at 24 V is the headline figure for the contact set — it handles the typical pilot-duty loads (PLC outputs, relay coils, indicator lamps) found in a control panel. The contact reliability spec — one incorrect switching operation per 100 million operations at 17 V, 1 mA — means it also handles low-energy signals without the oxidation problems that plague general-purpose relays in dry circuits.
Mounting and panel fit
Fastens with screw or snaps onto a DIN rail — both methods are supported. The 45 mm width and 114 mm depth fit the standard Size S00 footprint, so it drops into the same slot as other SIRIUS contactors and auxiliary blocks. Mounting position is flexible: ±180° rotation on a vertical surface, plus ±22.5° tilt forward or backward. The IP20 front protection means it's safe for finger contact inside an enclosed panel, but not for washdown or outdoor exposure. Wire range is 0.25 to 2.5 mm² solid, which covers the common control-circuit sizes.
Environmental and compliance
Operating temperature range is -25 to +60 °C; storage and transport extend to -55 to +80 °C. Shock resistance is 10 g at 5 ms and 5 g at 10 ms. The part carries a RoHS substance prohibition date of July 1, 2006, indicating compliance with the original RoHS directive.