Understanding the 1746-OA16 in Modern Automation
When designing or upgrading a control system, selecting the right output module is critical for reliable operation. The Allen-Bradley 1746-OA16 is a digital AC output module within the SLC500 family, engineered to handle discrete switching tasks in industrial environments. This module provides sixteen output channels organized into two groups of eight, delivering 120/240 VAC nominal output with a voltage range of 85 to 265 VAC.
For engineers seeking a proven solution for AC load control, the 1746-OA16 offers a balance of performance and simplicity. Its design integrates filter circuitry and optical coupling to reduce signal noise, enhancing system stability. As part of the SLC500 platform, it supports both local and remote I/O configurations, making it adaptable to various automation architectures.
Key Technical Specifications
The 1746-OA16 operates with an output delay time of 11.0 ms from OFF to ON and 1 ms from ON to OFF, ensuring predictable response in sequencing applications. Each output point can handle a continuous current of 0.50 A at 30 °C and 0.25 A at 60 °C, while the maximum continuous current per module reaches 8.0 A at 30 °C and 4.0 A at 60 °C. The module draws 0.370 A from the backplane at 5.1 Volts.
Additional specifications include an OFF-state leakage current of 2 mA and a load current of 10 mA. The step response is rated at 60 milliseconds in and 2.5 milliseconds out. These parameters allow engineers to accurately assess the module's suitability for their specific load and timing requirements.
Application Scenarios and Use Cases
In manufacturing facilities, the 1746-OA16 is commonly used to control AC-powered devices such as motor starters, solenoid valves, and indicator lights. Its two-group output architecture simplifies wiring and troubleshooting, especially in applications where loads are physically separated. For example, in a packaging line, one group can manage conveyor start/stop signals while the other handles reject gate actuators.
The module also fits well in HVAC control systems, where it can switch fans, pumps, or damper actuators. The wide operating voltage range of 85 to 264 VAC accommodates varying line conditions, reducing the risk of nuisance trips. Engineers appreciate the removable terminal blocks, which allow module replacement without disconnecting field wiring, minimizing downtime during maintenance.
Compatibility and Integration
The 1746-OA16 integrates seamlessly with SLC500 programmable logic controllers (PLCs) and can also be used with CompactLogix and ControlLogix programmable automation controllers (PACs) as remote I/O. It occupies a single slot in the chassis and consumes 16-bit I/O memory. There is no inherent limit on the number of modules in a system, provided the power supply can deliver the required backplane current.
Output status is indicated by LED indicators on the module face, simplifying diagnostics. The module's output values are accessible via ladder logic programming, enabling straightforward integration into existing control programs. For engineers migrating from older systems, the 1746-OA16 offers a familiar form factor and electrical characteristics.
Frequently Asked Questions
What is the maximum continuous current per output point on the 1746-OA16?
At 30 °C, each output point can handle 0.50 A continuously. At 60 °C, the rating derates to 0.25 A per point.
Can the 1746-OA16 be used with ControlLogix controllers?
Yes, the module can be installed as remote I/O with ControlLogix and CompactLogix PACs, in addition to SLC500 processors.
What is the OFF-state leakage current of this module?
The OFF-state leakage current is 2 mA, which should be considered when driving sensitive loads.
Does the 1746-OA16 require external wiring for each output group?
The module has two groups of eight outputs each, and each group has its own common terminal. Wiring should follow the group configuration as specified in the user manual.
Company Strength and Supply Assurance
Petro Auto Tech specializes in providing authentic industrial automation components, including the Allen-Bradley 1746-OA16. With a focus on quality and availability, we help engineers and procurement professionals source the right parts for their control systems. Please verify current lifecycle status and availability with Petro Auto Tech before ordering.
