The Siemens 3RB1015-2SB0 is an electronic overload relay in the SIRIUS family, rated 3...12 A, Class 20 trip curve, with screw terminals and manual reset only. It mounts directly on a size S00 contactor for motor protection in a control panel.
Class 20 means the relay trips within 20 seconds at 600% of the set current — standard for general-purpose motor starting where the inrush transient is brief. The 3...12 A range covers small motors (roughly 0.75 to 5.5 kW at 400 V). Manual reset only: the relay latches on trip and must be physically reset at the panel; there is no auto-reset option, so factor that into the restart sequence for an unattended line. Size S00 is the smallest SIRIUS contactor frame. The relay clips onto the contactor without additional wiring for the power circuit — the overload's through-holes align with the contactor's load-side terminals. Screw connections accept 0.5 to 4 mm² stranded or solid conductors.
Deployment context
Intended for DIN-rail-mounted contactor assemblies in motor control centers or standalone starter enclosures. The manual-reset button protrudes from the relay face; ensure panel clearance for access after installation. No auxiliary contact block is included — if remote trip indication is needed, order a separate 3RB1900-2A series accessory.