The 3RB1246-1QM10: The 6.3-25 A range covers small to medium motor loads — think fractional-horsepower pumps, fans, and conveyors up to about 11 kW at 400 V. The adjustable Class 5-30 trip curve lets you match the overload response to the motor's thermal time constant: Class 5 for submersible pumps that need fast trip, Class 30 for high-inertia loads like centrifuges. The S00/S0 frame size means it fits the compact footprint used in Siemens motor starter assemblies and individual mounting on DIN rail or panel. Control voltage at AC 220-240 V is standard for European control circuits; verify your panel's control voltage before specifying.
The current transformer on the main circuit means no separate CTs needed — the relay senses motor current directly through the power pass-through. Screw terminals on the auxiliary side accept 0.2-2.5 mm² stranded or solid wire. The monostable output drops out on a trip, so the relay defaults to a safe state on power loss.