What it is and what it does
The Siemens 3RB1036-2QB0 is a solid-state overload relay from the SIRIUS 3RB1 series, sized for motor protection in the 6 to 25 A range. It mounts directly onto a contactor, uses screw terminals, and is a size S2 frame. The Class 20 trip curve means it allows up to 20 seconds at 600% of the full-load current before tripping — the standard for standard-start induction motors driving pumps, fans, and conveyors where the start is not prolonged. The manual-automatic reset selector gives the commissioning engineer or MRO planner a choice: manual reset forces a local inspection after a trip (right for unattended or hazardous zones), while auto reset restarts the motor once the relay cools — useful for remote or hard-to-access installations where a nuisance trip shouldn't stop production.
Sourcing and lifecycle reality
Because it is a current-production part, the sourcing posture is straightforward: quoted to order against an RFQ. No broker or surplus channel is needed — the standard Siemens supply chain covers it.
Mounting and integration
The S2 frame size and screw connection are designed for direct mounting onto a matching SIRIUS contactor, forming a compact motor starter assembly on a DIN rail or mounting plate. The screw terminals accept standard power and control wiring — no special tooling needed for panel integration.