The Siemens 3RU2116-4AC0-ZW97 is a SIRIUS thermal overload relay in Size S00, designed for motor protection in control panels. Its CLASS 10 trip curve means it will trip within 10 seconds at 7.2x the set current — the standard for protecting standard induction motors during start-up, where the inrush transient needs to ride through without nuisance tripping. The relay mounts directly onto a contactor (contactor mounting fastening method), so it integrates as a single assembly on the DIN rail, saving panel width.
At 45 mm wide and 87 mm tall, the S00 frame fits tightly in crowded enclosures. The main circuit uses spring-loaded terminals — no screw torque to verify, just strip and push. The auxiliary switch is integrated, so there's no separate add-on block needed for the trip signal. The relay can be mounted in any position, which helps when the panel layout forces a horizontal or inverted orientation.
The auxiliary contact ratings cover multiple control voltages: 2 A at 24 V, 3 A at 120 V, 2 A at 230 V, and 1 A at 400 V. That means the same relay can signal a PLC input at 24 VDC or a contactor coil at 230 VAC without derating the contact. The rated insulation voltage is 690 V, matching the maximum AC-3e rated voltage of 690 V — so it's suited for 400 V and 690 V motor circuits common in European and export panels.