Product Description:

The 3DI425.6 is a digital input module produced by B & R Automation for the System 2005 Controllers series. The unit occupies one slot on a BP200, BP201, or BP210 base plate and converts field-level sensor states into logic-level signals for the CPU. By integrating optocoupler isolation, the module allows industrial machinery to monitor switches, proximity detectors, and relay contacts without transferring ground potential or noise into the control backplane.

This module offers 32 discrete inputs arranged in 8 × 4 groups. Each channel presents 4 kΩ of input resistance and is intended for a nominal supply of 24 VDC. The threshold range spans 5 to 15 V, so voltages below the low limit (<5 V) are read as logical 0 while voltages above the high limit (>15 V) are accepted as logical 1. Input-to-CPU and group-to-group paths are isolated by optocouplers to block fault currents between external circuits. Typical propagation delay is 10 ms, allowing reliable detection of slowly changing or steady contacts, and wiring can be configured for either sink or source topology to match the attached sensors.

The circuitry tolerates transients up to 30 VDC and still guarantees error-free operation; even at that ceiling the worst-case response remains 12 ms. Internal logic and LED indicators draw no more than 6 W at full load, minimizing heat inside densely packed cabinets. A compact outline of 285 × 40 × 185 mm permits stacking multiple modules on the chosen base plate while maintaining uniform airflow. Together with optically isolated buses and selectable wiring direction, the design completes the discrete input function for machines that must capture field signals under varied voltage, timing, and mounting constraints.