Allen-Bradley 1746-OW16 Relay Output Module

The Allen-Bradley 1746-OW16 is a 16-point relay output module within the SLC 500 I/O family, designed to provide reliable control for AC and DC output loads. This module bridges logic-level signals from the controller to field devices such as solenoids, indicators, and contactors, using mechanical relay outputs for maximum isolation and flexibility across voltage types.

Its ability to switch both AC and DC loads makes it a versatile choice for mixed-control environments in manufacturing, utilities, and process industries. The 1746-OW16 is known for its robust design, high surge tolerance, and field-proven reliability, making it one of the most widely used output modules in SLC 500 systems.

Technical Specifications

Common Industrial Applications

The 1746-OW16 is ideal for applications where electrical isolation, mixed-voltage operation, and high-load switching are required. It is frequently found in:

• Manufacturing Control Panels – operating AC contactors, solenoid valves, and lamps.

• Process Control Systems – driving motor starters and alarms with diverse voltage levels.

• Material Handling Equipment – energizing mechanical relays, gates, and conveyors.

• Batch Processing Units – handling output control for valves and heaters.

• HVAC and Facility Automation – controlling dampers, fans, and lighting circuits.

Its electromechanical design makes it an excellent interface between low-voltage logic circuits and high-power actuators.

Engineering Advantages

• Dual-Voltage Flexibility: Supports both AC and DC loads for universal field compatibility.

• High Isolation: 1500V RMS isolation ensures safety and signal integrity in noisy environments.

• Durable Relay Contacts: Long operational life even under inductive loading conditions.

• Built-In LED Indicators: Simplify troubleshooting and maintenance with clear visual feedback.

• Compact and Modular: Fits seamlessly into SLC 500 chassis, saving space in control enclosures.

• Versatile Load Handling: Capable of switching resistive, inductive, and capacitive loads efficiently.

FAQ

1. Can each output handle both AC and DC?

   Yes, each relay contact can switch either AC or DC loads independently.

2. Are outputs isolated from one another?

   Yes, each output is isolated, allowing different voltage sources per channel.

3. What type of relay contacts are used?

   Single-pole, single-throw (SPST-NO) Form A mechanical relays.

4. Is external suppression required for inductive loads?

   Yes, proper snubber or flyback diodes are recommended to protect contacts.

5. How are the outputs protected from overload?

   External fusing should be installed for each output group or device.

6. Can this module be used with PLC-5 systems?

   Not directly; it is designed for SLC 500 chassis but can connect via 1747-ASB remote adapter.

7. Is it hot-swappable?

   No, power should be turned off before inserting or removing the module.

8. What is the expected relay life?

   Typically 100,000 cycles at rated load, or up to 1,000,000 cycles at light load.

9. Does it support diagnostics over network?

   No built-in diagnostics; module status is indicated by local LEDs.

10. Can mixed load types be connected simultaneously?

    Yes, each output can control a unique voltage or load type independently.