Product Overview

Designed for high-density control applications, the Allen-Bradley 1769-OB32T is a discrete output module.
It features Thirty-Two (32) sourcing output channels with a nominal voltage of 24VDC.
Each channel provides solid-state sourcing output for reliable switching performance.
This module works with 1769 CompactLogix controllers and also with MicroLogix 1500 controllers.
Because of its high channel count, it suits applications requiring many output points.
The 1769-OB32T occupies only a single slot in the 1769 assembly or MicroLogix expansion bank.
With its open-type enclosure, however, it requires installation within a larger control cabinet.

Technical Specifications

Output Characteristics

The Allen-Bradley 1769-OB32T provides 32 sourcing output channels for controlling field devices.
Nominal output voltage is 24VDC , which matches standard industrial load requirements.
Minimum ON-state voltage equals 10.2 VDC for reliable switching under brownout conditions.
Maximum ON-state voltage reaches 26.4 VDC during normal operation.
Maximum continuous output current per point equals 2.0 A for each individual channel.
For the entire module, maximum continuous output current reaches 4.0 A total.
Surge current capability is 2.0 A for 10 ms , repeatable every 2 seconds.
Maximum ON-state voltage drop is 0.3 VDC at 0.5 A , ensuring efficient power delivery.

Current and Leakage

Minimum ON-state current requirement equals 1.0 mA for proper output switching.
Maximum OFF-state leakage current measures 0.1 mA at 26.4 VDC .
This low leakage prevents false triggering of sensitive high-impedance loads.
Thus, the 1769-OB32T works well with solid-state relays and small indicators.

Response Times

Output delay for ON transition equals 0.5 ms , enabling fast response to control commands.
Output delay for OFF transition equals 4 ms , providing controlled turn-off behavior.
Consequently, this module handles high-speed output applications such as positioning systems.
Note that these delays exclude controller scan time and backplane communication overhead.

Power Requirements

Backplane current draw equals 220 mA at 5.1 VDC for power consumption from the rack.
Maximum power dissipation reaches 1.10 Watts , which helps with thermal management.
Maximum thermal dissipation equals 4.76 Watts under full load conditions.
The Allen-Bradley 1769-OB32T has a power supply distance rating of 8 modules .
Therefore, mount this module within eight slots of the power supply for reliable operation.
For longer distances, add an I/O power supply to the backplane as needed.

Physical Characteristics

Dimensions and Weight

The 1769-OB32T weighs approximately 230 grams (0.51 lb) for lightweight handling.
Dimensions measure 118 x 35 x 87 mm (4.65 x 1.38 x 3.43 in.) for compact installation.
Slot width is single slot , which allows efficient rack space utilization.
Shipping weight equals 2 lbs with dimensions of 8 x 8 x 5 inches for transport.

Terminal and Wiring

Replacement terminal block part number is 1769-RTBN18 for convenient field service.
Replacement door part number is 1769-RD , providing terminal protection against contamination.
For solid conductors, wire size ranges from 22 to 14 AWG .
For stranded conductors, wire size ranges from 22 to 16 AWG instead.
Terminal screw torque specification equals 0.68 Nm (6 lb-in) for secure connections.
Wire type must be Copper rated at 90 degrees Celsius to meet safety standards.

Mounting Options

The Allen-Bradley 1769-OB32T supports both DIN rail and panel mounting methods.
DIN rail mounting offers quick installation and convenient removal capabilities.
In contrast, panel mounting provides greater resistance to shock and vibration.
Use the integrated mounting tabs for panel installation with appropriate screws.
For DIN rail, simply snap the 1769-OB32T onto standard 35 mm rail until it clicks.

Environmental Specifications

Temperature and Humidity

Operating temperature ranges from 0 to 60 °C (32 to 140 °F) for normal use.
Storage temperature spans from -40 to 85 °C (-40 to 185 °F) for long-term preservation.
The 1769-OB32T operates reliably across these temperature ranges without derating.

Vibration and Shock

Operating vibration rating is 5g at 10 to 500 Hz , suitable for industrial environments.
Operating shock tolerance reaches 30g for panel-mounted configurations.
For DIN rail-mounted modules, however, shock tolerance is lower than panel mounting.
Hence, panel mounting is strongly recommended for high-vibration applications.

Insulation Rating

The Allen-Bradley 1769-OB32T has IEC Class 2 reinforced insulation for safety.
This insulation provides reliable protection against electrical shock hazards.
Additionally, it isolates the outputs from the backplane and logic circuits.

Compatibility

Controllers

The 1769-OB32T works seamlessly with all 1769 CompactLogix controllers.
It also works with the MicroLogix 1500 controller system without issues.
For MicroLogix 1500, install the module in an available expansion slot.

Power Supplies

The module observes the 8-module power supply distance rating for proper operation.
Compatible power supplies include standard 1769 series units from Rockwell Automation.
For systems exceeding 8 modules, install an additional I/O power supply strategically.

Installation Guidelines

First, verify the power supply distance rating before starting installation.
Select a slot within eight modules of your system power supply for compliance.
Next, install the Allen-Bradley 1769-OB32T into the 1769 backplane firmly.
Secure the module using the integrated locking mechanism on the side of the housing.
For DIN rail mounting, snap the module onto 35 mm rail until it clicks into place.
For panel mounting, use screws through the mounting tabs provided with the module.
Connect field wiring using 22-14 AWG solid or 22-16 AWG stranded copper wire.
Torque terminal screws to 0.68 Nm (6 lb-in) to ensure secure connections.
For sourcing outputs, wire the load between the output channel and 0V DC common.
After wiring, configure the 1769-OB32T in your controller's I/O tree before use.

Output Wiring Guide

For sourcing output configuration, the module supplies current to connected loads.
Connect the load positive terminal to the desired output channel.
Connect the load negative terminal to the external 0V DC supply common.
The Allen-Bradley 1769-OB32T output turns ON when the channel is logically energized.
For inductive loads such as relays or solenoids, install a suppression diode across the load.
This diode prevents harmful voltage spikes from damaging the output transistor.

Package Contents

• 1 x Allen-Bradley 1769-OB32T discrete output module

• 1 x Replacement door (1769-RD) for terminal protection

• 1 x Module identification label for field marking

• 1 x Installation instruction sheet for reference

• 1 x Terminal block cover (pre-installed)

Frequently Asked Questions (FAQ)

1. Can the 1769-OB32T sink current instead of sourcing?

No, the Allen-Bradley 1769-OB32T is sourcing only. For sinking outputs, use the 1769-OB32 or 1769-OB16 models from Rockwell.

2. What is the maximum total current for all 32 outputs?

The 1769-OB32T has a module limit of 4.0 A total. Additionally, do not exceed 2.0 A on any single channel.

3. Can I use this module with a 12VDC load?

The minimum ON-state voltage is 10.2 VDC on the 1769-OB32T . However, 12VDC operation may affect long-term switching reliability.

4. Why does my output stay on after turning it off?

Check the OFF-state leakage current of the 1769-OB32T . The 0.1 mA leakage may keep high-impedance loads partially energized.

5. Is the 1769-RTBN18 terminal block included with this module?

No, the Allen-Bradley 1769-OB32T does not include the terminal block. Order 1769-RTBN18 separately as a spare or replacement part.