IP2321-B518-0000 by Beckhoff

The IP2321-B518-0000 is a compact box unit produced by Beckhoff within the IP Compact Box Units series. Designed for decentralized installation directly on machinery, the module combines digital sensing and actuation so a controller can monitor field signals and switch loads of up to two amperes without a control cabinet. In industrial automation, it serves as a rugged interface that connects sensors, actuators, and the higher-level bus in environments that require sealed housings. Its compact format allows installation near field devices, reducing the length and complexity of individual sensor and actuator wiring.

It integrates a CANopen interface with an integrated tee connector, allowing the module to be daisy-chained without external couplers. The unit provides four inputs and four outputs, with each input using a 3.0 ms filter to suppress contact bounce before data reaches the process image. Each output can deliver 2.0 A per channel, and the aluminum-filled housing has an IP65/IP66/IP67 protection rating that supports washdown and outdoor installations. The control and fieldbus circuits are galvanically isolated and protected against reverse polarity. Internal mapping provides a 4-bit input image and a 4-bit output image to the host, which minimizes the amount of process data transferred during each cycle. Load current consumption is 30 mA per channel, and the outputs are short-circuit-proof to simplify system protection.

The module operates from a 24 VDC supply routed through twin M8 power connectors. Sensor power is available at 0.5 A per channel, allowing proximity switches or photoelectric sensors to operate without extra power terminals. If a wiring fault occurs, an internal electronic fuse limits the affected branch to 4.0 A and resets automatically after the fault is cleared. Field devices attach through M8 screw-in connections, which permit quick disconnection while maintaining the housing seal. The module has a total switching capacity of 4 A, providing sufficient capacity for multiple solenoid loads during machine indexing. The sealed connections and decentralized layout also help protect signal paths in machinery exposed to dust, moisture, and routine cleaning.