Rockwell / Allen-Bradley 1794-IB16 FLEX I/O 24 VDC 16 Sink Input Module

The Rockwell Automation / Allen-Bradley 1794-IB16 is a FLEX I/O 16-channel digital input module that interfaces 24 VDC sinking input signals directly to a programmable logic controller. Operating across the 10 to 31.2 VDC input range, the module delivers real-time discrete signal acquisition with per-channel LED diagnostics. Each input channel carries a nominal load of 8.0 mA at 24 V DC, with configurable on-state thresholds from 10 to 31.2 VDC and off-state maximum of 5 VDC.

Thermal output reaches 11.9 BTU/hr at maximum rated voltage. The module mounts via DIN-rail to a required TB3/TB3S terminal base using screw terminal connections. Three network protocols

ControlNet, DeviceNet, and EtherNet/IP - enable integration into diverse industrial automation architectures.

Rated for 0 to 55 °C operating temperature and 5 to 95% non-condensing humidity, the module withstands 5 g vibration (10–500 Hz) and 30 g operating shock. Not rated for safety-critical applications.

Technical Specifications

• Input Channels: 16 sinking inputs


• Nominal Voltage: 24 VDC


• Input Range: 10 to 31.2 VDC


• On-State Current: 2.0 to 12.0 mA (8.0 mA nominal @ 24 V DC)


• On-State Voltage: 10 to 31.2 VDC


• Off-State Voltage: Maximum 5 VDC


• Off-State Current: Maximum 1.5 mA


• Input Impedance: 4.6 kΩ nominal


• Flexbus Current Draw: 30 mA @ 5 V DC


• Max Power Dissipation: 6.1 W @ 31.2 V DC


• Thermal Output: 11.9 BTU/hr @ 31.2 V DC


• Operating Temperature: 0 to 55 °C


• Storage Temperature: -40 to 85 °C


• Humidity (Non-Condensing): 5 to 95%


• Vibration: 5 g from 10 to 500 Hz


• Operating Shock: 30 g peak (11±1 ms pulse)

Key Features

• 16 individual LED status indicators for channel-level diagnostics


• Screw terminal connectivity via TB3/TB3S base


• Multi-protocol support (ControlNet, DeviceNet, EtherNet/IP)


• DIN-rail and panel mounting capability


• Broad input voltage tolerance from 10 to 31.2 VDC

Typical Applications Discrete sensor input acquisition, industrial process control, machine automation, and networked I/O expansion in Allen-Bradley PLC environments.

Compatibility & Integration Designed for FLEX I/O architecture with support for ControlNet, DeviceNet, and EtherNet/IP communication adapters. Requires TB3/TB3S terminal base. Certifications include CE, CSA, CUL, UL, C-TICK, KC, GOST, and MARINE.