Overview
The Allen-Bradley 1794-ASB2 is a remote I/O adapter module within the FLEX I/O series, designed as a compact power supply and network interface for distributed control architectures. This Remote I/O Adapter is part of the Flex I/O series, and supports integration of up to two modules. Unlike the larger 1794-ASB (which accommodates 8 modules), the ASB2 variant is optimized for space-constrained remote I/O applications where a smaller footprint and lower module capacity are sufficient.
Key Features
- Module capacity supports integration of up to two modules
- Communication capabilities include adjustable speeds of 57.6, 115.2, and 230.4 Kbps
- Maximum FlexBus current of 640 mA
- Mounts on a DIN rail with indicators for status updates and fault warnings
- UL Listed Industrial Control Equipment, certified for US and Canada
- Uses either 22 to 12 AWG or 22 to 16 AWG wires
Technical Specifications
The 1794-ASB2 delivers robust performance across a range of industrial environments with standardized voltage and communication parameters:
- Input Voltage: 19.2 to 31.2 V DC (nominal 24 V DC)
- Maximum Output Current: 640 milliAmps at 5 Volts DC
- Current Draw: 330 milliAmps with maximum power dissipation of 4.6 Watts
- Communication Rates: 57.6, 115.2, and 230.4 Kbps
- I/O Module Capacity: 2 modules
- Mounting: DIN rail mount
- Weight: 0.40 lbs
- Status Indicators: LED indicators flash or glow steadily in green or red
Typical Applications
The 1794-ASB2 is widely deployed in manufacturing and process control environments requiring remote distributed I/O:
- Discrete manufacturing with remote sensor arrays and actuator control
- Machine-to-PLC networks across production floors
- Packaging and material handling systems
- Food and beverage processing with remote control nodes
- Assembly lines requiring flexible I/O expansion without main rack proximity
- Legacy PLC-5 system upgrades and expansions
Compatibility & Replacements
Compatible With
- PLC-5 processors
- FLEX I/O remote module ecosystem
- FlexBus serial communication networks
- Industrial automation systems requiring distributed I/O architecture
Replaces / Drop-In Replacement For
- Earlier revisions of 1794-ASB2 (Series A, B, C variants)
- Custom-built remote I/O adapters in legacy PLC-5 systems
- Verify compatibility with your system integrator before ordering to ensure proper configuration and firmware support
Works With
- FLEX I/O I/O modules (limit 2 for ASB2)
- RSLogix 5000 programming environment
- FlexBus serial protocol (57.6, 115.2, 230.4 Kbps)
- Allen-Bradley control systems and SLC platforms
- Industrial Ethernet-to-FLEX I/O gateway configurations
