The 3RB1262-0LB20: The 200...820 A current range covers large motor loads — think 400 kW+ induction motors at 400 V. The adjustable trip class (5...30) lets you match the relay's thermal characteristic to the motor's starting profile: Class 5 for short acceleration times on low-inertia loads like pumps, Class 30 for high-inertia loads like centrifuges or crushers that take longer to spin up. The built-in ground fault detection on a DC 24 V control circuit means it can signal a ground leak without a separate protection module — useful on ungrounded IT systems or where you want an early warning before a phase-to-ground fault escalates.
Deployment Context
This relay mounts to a contactor assembly or individually on a panel. The busbar main circuit connection is typical for high-current motor control centers (MCCs) where bolted bus connections replace cable lugs. The screw-terminal auxiliary circuit is standard for control wiring. The S10/S12 frame size means it pairs with the corresponding SIRIUS contactor for a coordinated motor starter package.