Allen-Bradley 1756-OB32 ControlLogix 32-Point 12/24V DC Digital Output Module

Product Description

The 1756-OB32 is a high-density discrete output module designed for the Allen-Bradley ControlLogix platform. Featuring 32 sourcing outputs, this module provides a robust interface for driving a large number of low-power DC loads—such as solenoid valves, actuators, and pilot lights—from a single chassis slot.

By utilizing high-density electronics, the 1756-OB32 (Ser A/B) significantly reduces the physical footprint of the control system while maintaining high operational reliability. The module supports electronic fusing to protect internal circuitry from overcurrent conditions and provides comprehensive diagnostics via the Studio 5000 environment. Its non-isolated design is optimized for applications where multiple outputs share a common DC power source, ensuring efficient wiring and simplified power distribution.

Detailed Technical Specifications

• Model Number: 1756-OB32

• Brand: Allen-Bradley / Rockwell Automation

• Output Type: 12/24V DC Sourcing (Sourcing Output)

• Number of Outputs: 32 Points (16 points per group)

• Operating Voltage Range: 10V DC to 31.2V DC

• Maximum Output Current per Point: 0.5 A @ 50°C; 0.35 A @ 60°C

• Maximum Output Current per Module: 16 A @ 50°C; 10 A @ 60°C

• On-State Voltage Drop (max): 200 mV DC @ 0.5 A

• Backplane Current (5.1V DC): 300 mA

• Backplane Current (24V DC): 2 mA

• Surge Current per Point: 1.0 A for 10 ms (repeatable every 2 seconds)

• Removable Terminal Block (RTB): 1756-TBCH or 1756-TBSH (36-pin)

• Operating Temperature: 0 to 60 degrees Celsius (32 to 140 degrees Fahrenheit)

• Isolation Voltage: 250V (continuous), Basic Insulation Type

• Net Weight: 0.28 kg (0.61 lbs)

Industrial Application Scenarios

The 1756-OB32 is an ideal solution for high-volume discrete control tasks, such as managing complex pneumatic manifolds in automotive assembly or controlling large arrays of status indicators in food and beverage packaging lines. Its 32-point density allows for extensive I/O expansion in compact control cabinets.

Professional FAQ

• Does this module include electronic fusing?

• Yes, the 1756-OB32 features electronic protection that helps prevent damage to the module during a short circuit or overload condition on the field side.

• Is the Removable Terminal Block (RTB) included?

• No, the RTB is sold separately. You must specify either the 1756-TBCH (cage clamp) or 1756-TBSH (spring clamp) to complete the installation.