Overview
The Allen-Bradley 1746-OA8 is an SLC 500 discrete AC output module with eight output channels in two groups of four channels each. Used to energize electrical loads that operate at an operating voltage range of 85-264 VCA with frequency of 47-63 Hz, this module provides 1500V AC isolation between the field side and logic side for enhanced safety. The module fits to any available slot of the 1746 chassis except the first slot which is reserved for the SLC 500 processor, and must be attached to the chassis when power is not actively supplied as this module does not support Removal and Insertion Under Power (RIUP).
Key Features
- Nominal output voltages of 120VAC and 240VAC with wide operating range
- ON signal delay of 1 ms for resistive load and maximum OFF delay signal of 11 ms for resistive load
- LED Indicators provide visual status for each output channel
- Fits into any available I/O slot of an SLC 500 chassis
- 185 mA backplane current draw @ 5VDC
- Compact single-slot form factor for space-efficient installations
Technical Specifications
- Output Voltage: 85-264 VAC @ 47-63 Hz
- Number of Outputs: 8 channels in 2 groups of 4
- Continuous Output Current (per channel): 1.0 A @ 30°C or 0.50 A @ 60°C
- Maximum Continuous Output Current (module): 8.0 A @ 30°C and 4.0 A @ 60°C
- Surge Current: 10A for 25ms
- ON-State Output Voltage Drop: 1.50V @ 1.0 A
- Maximum OFF-State Leakage: 2 mA
- Minimum Load Current: 10 mA
- Backplane Current: 185 mA @ 5VDC
- Signal ON Delay: 1 ms (resistive load)
- Signal OFF Delay: 11 ms (resistive load)
- Operating Temperature: 0 to 60°C (32 to 140°F)
- Storage Temperature: -40 to 85°C (-40 to 185°F)
- Relative Humidity: 5-95% non-condensing
- Isolation: 1500V AC isolation between field and logic sides
Typical Applications
Widely used in industries such as manufacturing, material handling, packaging, and building automation. The module is suitable for controlling AC magnetic contactors, solenoids, indicator lights, and other AC loads in industrial automation applications. With the voltage rating, it may be used directly to energize magnetic contactors unlike DC output modules which may need an interposing relay to operate, making it a practical solution for operating AC loads with low current requirement.
Compatibility & Replacements
The 1746-OA8 is compatible with all SLC 500 fixed and modular processor systems, including SLC 5/01, SLC 5/02, SLC 5/03, SLC 5/04, and SLC 5/05. The module integrates seamlessly into 1746 chassis configurations. As a digital AC output module for the SLC 500 platform, the 1746-OA8 offers reliable discrete output control with proven industrial performance. Used and refurbished units remain in high demand for legacy system upgrades and expansions, with fast shipping typically available from authorized distributors.
