Description
Description
The Allen-Bradley 1746-OW8 is a high-performance discrete output module designed for the SLC 500 programmable logic controller system. This module features eight (8) normally open (N.O.) electromechanical relay contacts, providing robust "dry contact" switching capabilities. By utilizing mechanical relays, the 1746-OW8 allows for the control of both AC and DC loads within a single module, making it an essential interface component for applications requiring the integration of disparate voltage levels, such as 120V AC motor starters and 24V DC pilot lights.
Features
- Eight (8) normally open (N.O.) relay output points.
- Organized into two (2) isolated groups of four outputs each, allowing for independent power source selection per group.
- Zero off-state leakage current, ideal for high-impedance loads sensitive to leakage.
- Compatible with a wide range of AC and DC operating voltages.
- Designed for seamless integration into the SLC 500 chassis backplane.
Applications
This module is widely utilized in industrial automation environments for interfacing the SLC 500 controller with field devices. Common applications include controlling motor starters, solenoid valves, contactors, and indicating lamps where galvanic isolation or the ability to switch mixed voltage types is required.
Technical Specifications
| Brand |
Allen-Bradley |
| Product Line |
SLC 500 |
| Module Type |
Digital Relay Output (Normally Open) |
| Number of Outputs |
8 (2 groups of 4) |
| Operating Voltage (AC) |
5 to 265V AC (47 to 63 Hz) |
| Operating Voltage (DC) |
5 to 125V DC |
| Backplane Current (5V DC) |
85 mA |
| Backplane Current (24V DC) |
90 mA |
| Signal Delay (On/Off) |
10.0 ms (max resistive load) |
| Total Heat Dissipation |
3.7 Watts |
| Heat Dissipation per Point |
0.138 Watts |
Installation Guidelines
- Ensure the SLC 500 system power is disconnected before inserting or removing the module from the chassis.
- The module should be seated firmly into the chassis slot to ensure proper backplane connection.
- Use appropriate wire gauges and ensure all terminal screws are tightened to the specified torque to prevent loose connections.
- Maintain proper cable routing to minimize electromagnetic interference (EMI) from high-voltage lines.
- Ensure the environment is within the specified temperature and humidity ratings for the SLC 500 system.
- Handle with care to prevent electrostatic discharge (ESD) damage to the module circuitry.
FAQ
Does the 1746-OW8 allow for mixing AC and DC loads?
Yes, because the module is organized into two isolated groups of four outputs, you can connect different voltage sources to each group, allowing for the simultaneous control of AC and DC loads.
Is there any leakage current with this module?
No, the 1746-OW8 uses electromechanical relays, which provide a physical air gap when open, resulting in zero off-state leakage current.
