Overview
The Allen-Bradley 1794-IA8 is a discrete digital input module from the FLEX I/O 1794 series, engineered for reliable AC signal acquisition in distributed automation systems. This 8-point input module converts 120VAC field signals to logic levels compatible with Rockwell Automation controllers and gateway devices. The non-isolated input design simplifies wiring while the compact open-style enclosure enables flexible mounting on standard 1794 terminal base units.
Key Features
- 8 non-isolated inputs with AC signal conversion to appropriate logic level
- 8 yellow status indicator LEDs for real-time input monitoring
- Mounts on DIN rail or panel using terminal base units
- IP 20 environmental protection rating
- Approved for North American Hazardous Locations (Class 1, Division 2, Groups A, B, C, D)
- Supports multiple communication interfaces including DeviceNet, ControlNet, Profibus DP, and EtherNet/IP
Technical Specifications
| Input Points | 8 non-isolated digital inputs (0–7) |
| Input Voltage (Nominal) | 120VAC |
| Input Voltage Range | 85 to 132 Volts AC, 47 to 63 Hz |
| On-State Voltage | 65V AC minimum, 120V AC nominal, 132V AC maximum |
| Off-State Voltage | 43 Volts AC maximum |
| On-State Current (Max) | 14.32 milliamps |
| Power Dissipation | 4.5W maximum at 132VAC; 15.3 BTU/hour thermal dissipation |
| Filter Time (OFF→ON) | 8.4 milliseconds |
| Filter Time (ON→OFF) | 26.4 milliseconds |
| Operating Temperature | –4 to 131 degrees Fahrenheit (–20 to 55°C) |
| Storage Temperature | –40 to 185 degrees Fahrenheit (–40 to 85°C) |
| Isolation Voltage | 2150 Volts DC (1 second, system to user) |
| Dimensions | 3.7 × 2.7 × 3.7 inches |
| Wire Compatibility | 22 to 12 AWG stranded copper wire |
| Enclosure Type | Open-style |
| Certifications | C-TICK, CE, CSA, GOST, KC, MARINE, UL |
Typical Applications
The 1794-IA8 is commonly deployed in:
- Distributed I/O networks for process control and machine automation
- Safety function applications in industrial control systems
- Plant floor signal acquisition for hazardous and non-hazardous locations
- Replacement or expansion modules for existing FLEX I/O racks
- Remote I/O termination over EtherNet/IP and ControlNet networks
Compatibility & Replacements
Compatible With
- Terminal base units: 1794-TB2, 1794-TB3, 1794-TBN, 1794-TBNK
- Also compatible with 1794-TB3K, 1794-TB3SK, 1794-TBKD, 1794-TB3S terminal bases
- Rockwell ControlLogix, CompactLogix, and other controller platforms via FLEX I/O gateway
- EtherNet/IP, ControlNet, DeviceNet, Profibus DP networks
Replaces / Drop-In Replacement For
The 1794-IA8 (non-isolated) is distinct from the 1794-IA8I (isolated version). Verify your application requirements before substitution. The 1794-IA8 can replace other discontinued FLEX I/O 8-point AC input modules when mounted on compatible terminal bases.
Works With
- Rockwell Studio 5000 Logix Designer (ControlLogix, CompactLogix)
- FLEX I/O configuration tools and gateway modules
- EtherNet/IP, ControlNet, DeviceNet, Remote I/O, PROFIBUS DP, Interbus-S communication networks
- Allen-Bradley HMI platforms (PanelView, ThinManager)
