Overview
The 3RB2283-4AC1 is a Siemens overload relay with 3 poles, rated for a switching current of 630 A and offering adjustable trip classes 5, 10, 20 and 30. It is housed in an IP20 enclosure for stand-alone installation and carries ATEX Ex II (2) GD certification for use in potentially explosive atmospheres.
This overload relay protects motors by monitoring current and tripping on overload. The adjustable trip class — selectable between CLASS 5, 10, 20 and 30 — lets the user match the relay's thermal response to the motor's starting characteristics: a CLASS 10 setting suits standard induction motors, while CLASS 20 or 30 accommodates longer acceleration times such as on high-inertia loads.
Applications
The 3RB2283-4AC1 is used in motor control centres, pump and fan drives, conveyor systems, and other industrial machinery where three-phase motor protection is required. Its adjustable trip class makes it suitable for both standard and high-inertia loads, and the ATEX certification extends its use to hazardous-area installations such as chemical processing, oil and gas, and grain handling.