Allen-Bradley 1771-OBN 8-Point Digital Output Module

The Allen-Bradley 1771-OBN is an eight-point DC digital output module for the PLC-5 1771 I/O bus, designed to be mounted in a 1771-series I/O rack and to draw output power from a 10–30 V DC supply to control DC devices from the PLC. Each of the eight outputs is a sourcing (high-side) channel capable of delivering up to 0.5 A, with a per-group limit of 2 A and an overall module limit of 8 A, allowing multiple smaller loads to be driven directly while protecting the power rails; loads connected to the outputs should be wired to the return or 0 V, since the OB N outputs provide voltage and require a sink in the load circuit. As a Series B DC output module, the 1771-OBN is part of the 1771 DC Output Module family designed for PLC-5 systems and is compatible with 1771 I/O racks that support DC output modules, relying on the 1771 bus interface for addressing and signaling.