Allen-Bradley Compact I/O 1769-IQ32T 32-Point 24VDC Sink/Source Discrete Input Module

Module Overview

The 1769-IQ32T is a high-density discrete input module designed for the Allen-Bradley CompactLogix and MicroLogix 1500 controller families. Providing 32 independent input points in a single-slot footprint, this module is an ideal solution for applications requiring high I/O counts within limited cabinet space. The 1769-IQ32T is versatile, supporting both sinking and sourcing wiring configurations, and utilizes a high-density 40-pin connector to manage its extensive signal count.

Detailed Engineering Specifications

The 1769-IQ32T is engineered to interface with standard 24V DC field devices such as limit switches, pushbuttons, and electronic proximity sensors.

• Number of Inputs: 32 Points

• Voltage Category: 24 Volts DC

• Operating Voltage Range: 10 to 30 Volts DC

• Input Type: Sinking or Sourcing (User-defined by common wiring)

• Input Delay (Off-to-On): 8.0 milliseconds (typical)

• Input Delay (On-to-Off): 8.0 milliseconds (typical)

• Backplane Current Draw (5V DC): 170 mA

• Backplane Current Draw (24V DC): 0 mA (No 24V backplane draw)

• Power Dissipation: 4.5 Watts maximum

• Isolation Voltage: 75 Volts (Continuous), reinforced insulation type

• Hardware Termination: 40-pin high-density header

• Operating Temperature: 0°C to 60°C (32°F to 140°F)

• Physical Weight: 0.26 lbs (0.12 kg)

• Module Slot Width: 1 Slot

High-Density Wiring and Connectivity

Due to the 32-point density, the 1769-IQ32T does not use standard screw terminals on the module face. Instead, it requires a 40-pin high-density connector. For efficient field integration, engineers typically use a pre-wired cable (such as the 1492-CABLE series) to connect the module to a 1492 Interface Module (IFM). This setup simplifies troubleshooting and prevents wiring errors common with high-count discrete modules.

System Integration and Power Supply Distance

When planning a Compact I/O rack, it is critical to observe the Power Supply Distance Rating. The 1769-IQ32T has a distance rating of 8, meaning it must be located within eight slots of a 1769 power supply module (such as a 1769-PA2 or 1769-PB4). This ensures the 5V logic bus maintains sufficient voltage for the module's internal circuitry.

Technical FAQ

What is the difference between Sinking and Sourcing for the 1769-IQ32T?

The module is "bi-polar." If you connect the common terminal (DC COM) to the negative side of your power supply, the inputs are Sinking. If you connect the common to the positive side, the inputs are Sourcing. This flexibility allows the module to interface with virtually any DC sensor type.

Does this module include a removable terminal block (RTB)?

No. Because of the 32-point density, it utilizes a 40-pin header. You must purchase a compatible 40-pin connector kit or a pre-terminated 1492 cable assembly separately.

Can I use this module with a MicroLogix 1500 controller?

Yes. The 1769 Compact I/O platform is the expansion bus for the MicroLogix 1500. However, ensure your total power budget does not exceed the capacity of the MicroLogix base unit's power supply.