What it is and what it does
The Siemens 3RU1116-1KB0-ZX95 is a SIRIUS thermal overload relay in size S00, designed to protect three-phase motor circuits against sustained overcurrent by tracking the thermal replica of the motor winding. Trip Class CLASS 10 means it will open within 10 seconds at 7.2× the set current — fast enough to protect standard induction motors during a locked-rotor event. It mounts directly to the matching contactor (contactor mounting, not standalone DIN rail), saving panel width.
Fit and panel integration
Dimensions are 45 mm wide, 87 mm high, 78 mm deep — the S00 footprint that fits alongside S00 contactors without extra side clearance. Zero clearance required upwards, forwards, backwards, and downwards; only 6 mm at the side. Mounting position is flexible: vertical surface with ±135° rotation and ±45° tilt front/back, so it adapts to tight enclosures or angled backplates. Screw terminals on both main and auxiliary circuits accept 2× (0.5…1.5 mm²) solid or 2× (0.75…2.5 mm²) stranded (AWG equivalents: 2× 20…16 and 2× 18…14). IP20 on the front — protected against finger contact, not washdown.
Environmental and compliance
Operating temperature range is -20 to +70 °C; storage and transport span -55 to +80 °C. Rated for 100 % relative humidity during operation — condensation-laden cabinet air is fine. Shock resistance is 8g / 10 ms, typical for industrial panel-mounted gear. Surge voltage resistance rated at 6 kV. The ATEX approval (DMT 98 ATEX G 001) qualifies it for use in potentially explosive gas atmospheres when paired with an appropriate contactor and upstream protection. Lifecycle status is current production — no phase-out notice on this order code.