The Siemens 3RU7136-4FB0 is a SIRIUS thermal overload relay, size S2, rated 40 A operational current at 690 V AC/DC, Trip Class 10. It mounts directly onto a S2 contactor — no separate DIN-rail footprint needed — and protects a 3-phase motor against sustained overloads. Class 10 means it trips within 10 seconds at 7.2× the current setting, fast enough to protect standard induction motors during a stall without nuisance tripping on normal starting inrush.
Mounting and integration
Fastens directly to a S2 contactor (screw-type main circuit terminals top and bottom). Mounting position allows ±135° rotation on a vertical surface and ±45° tilt forward/back — flexible for tight panel layouts. Side spacing to grounded parts needs 6 mm minimum. Screw terminals for main circuit accept 2x (0.5…1.5 mm²) solid or stranded, torque 3–4.5 N·m. Auxiliary terminals take 2x (0.5…1.5 mm²) at 0.8–1.2 N·m.