The Siemens 3RU1116-1JB0-ZW98 is a SIRIUS thermal overload relay in Size S00 — the smallest frame in the SIRIUS family, sized for compact motor starter assemblies. It protects three-phase motors against overcurrent and phase failure, with a Trip Class 10 rating that clears a locked-rotor condition within 10 seconds at 7.2× setting current, standard for standard-duty induction motors driving pumps, fans, and conveyors.
Mounts directly to the contactor via the fastening method — no DIN rail required in the base assembly, though the contactor itself may be rail-mounted. The vertical mounting surface accepts ±135° rotation and ±45° tilt front-to-back, giving panel builders flexibility on orientation inside the enclosure. Clearance: 0 mm upwards, forwards, and backwards; 6 mm at the side; 0 mm downwards. That zero-clearance on five of six sides means it tucks tight against adjacent devices, but the 6 mm side gap is mandatory for heat dissipation — don't crowd that face. Terminals are screw-type on both main and auxiliary/control circuits. Solid and finely stranded with core-end processing: 2× (0.5…1.5 mm²) and 2× (0.75…2.5 mm²) per clamp. AWG equivalents for auxiliary contacts: 2× (20…16) and 2× (18…14). The finger-safe IP20 front protection means accidental contact during panel work is guarded against — no additional covers needed for the operator interface.
Power dissipation per pole is 2.2 W, totaling 6.6 W across three poles at rated current — a factor when sizing enclosure ventilation, especially in a sealed cabinet with multiple starters. Shock resistance rated at 8g for 10 ms, suitable for machine-mounted applications with moderate vibration. Surge voltage resistance at 6 kV gives coordination margin for industrial mains with common transients.