Honeywell 51303928-150 MC-TDID72 Digital Input Module

Core Technical Specifications

The 51303928-150 MC-TDID72 digital input module accepts thirty-two independent discrete signals from field sensors and switches. This unit measures 180 millimeters in height, 40 millimeters in width, and 170 millimeters in depth, with a total weight of approximately 0.58 kilograms. Each input channel operates at 24 volts DC with a nominal current of 7 milliamperes. The module features 1500 volts of galvanic isolation between the field inputs and the logic bus circuitry.

Input Performance and Signal Processing

The 51303928-150 MC-TDID72 detects on-state voltages from 15 to 30 volts DC with built-in hysteresis for noise immunity. It recognizes off-state signals between 0 and 5 volts DC as a valid low condition. The module filters electrical noise using a 1-millisecond debounce filter on every input channel. It includes LED indicators that show the real-time activation status of each input point. This module also supports high-speed pulse-capture for counting fast transient signals.

Physical Installation and Mounting

You can install this module into any standard Honeywell Series C backplane using its single-slot design. Its front panel includes a 50-pin D-sub connector for all field input wiring terminations. The unit’s 40-millimeter width enables high-density channel configurations in control cabinets. LED indicators display power presence and input status for each channel group. The module’s rugged housing provides effective protection against electromagnetic interference.

Memory and Data Management

The 51303928-150 MC-TDID72 stores input status data and diagnostic information in 2 kilobytes of internal dual-port RAM. It retains configuration parameters in 1 kilobyte of non-volatile EEPROM memory. This module maps each input channel to a specific bit address in the processor’s I/O table. It buffers time-stamped state changes for sequence-of-events recording. The unit also includes an input filtering configuration that you can adjust via software.

Power Distribution and Environmental Tolerance

This module draws a typical current of 160 milliamperes from the 5-volt DC backplane supply. It also requires a separate 24-volt DC field supply rated at 250 milliamperes for sensor power. The 51303928-150 MC-TDID72 operates reliably across a wide temperature range from -20 to 70 degrees Celsius. It withstands humidity levels between 5% and 95% without condensation. The unit provides 1500 volts of isolation between the field inputs and the logic bus.

Configuration and Diagnostic Functions

You can configure each input channel with programmable debounce settings from 0 to 20 milliseconds. The module supports both pulse-catch mode and change-of-state reporting for flexible applications. It provides open-wire detection through a built-in pull-up resistor network. The 51303928-150 MC-TDID72 also includes a loopback test feature for verifying channel integrity. These diagnostic capabilities reduce troubleshooting time and improve overall system availability significantly.