Overview
The Allen-Bradley 1794-OB16D is a Flex I/O discrete output module engineered for reliable control in industrial automation systems. This 16-point DC output module features integrated diagnostics functionality that detects, indicates, and reports open and shorted field devices or wiring—critical for troubleshooting in production environments. The module supplies 16 independent current-sourcing outputs rated at 24V DC nominal, with a maximum per-channel rating of 500 mA and 8 A module total.
Key Features
- 16 Current-Sourcing Outputs: Each rated at 500 mA per channel with 8 A total module capacity
- Integrated Diagnostics (D-Series): Monitors and reports field device faults, open circuits, and shorts in real time
- Hot-Swap Capable: Insert and remove modules under backplane power without system restart
- Wide Voltage Range: Operates 10–31.2 V DC, accommodating various power supply tolerances
- Compact DIN Mount: Open-style design with DIN rail mounting for flexible panel layouts
- Fast Response Time: 0.1 ms maximum output switching delay
Technical Specifications
- Output Type: 16-point DC sourcing, non-isolated
- Nominal Output Voltage: 24 V DC
- Output Voltage Range: 10–31.2 V DC (with 5% AC ripple tolerance)
- Per-Channel Output Current: 500 mA maximum
- Module Output Current (Total): 8 A maximum
- Output Delay (On-to-Off / Off-to-On): 0.1 ms maximum
- Off-State Leakage: 0.5 mA maximum per channel
- External Power Supply: 10–31.2 V DC, 56–78 mA @ nominal
- Maximum Power Dissipation: 4.8 W @ 31.2 V DC
- Operating Temperature: 0–55 °C (32–131 °F)
- Relative Humidity: 5–95% non-condensing
- Mounting Style: DIN rail, open enclosure
- Module Dimensions: 3.7 × 3.7 × 2.7 inches
- Weight: Approximately 78 grams
- Status Indicators: 16 yellow LEDs (one per output channel)
- Certifications: CSA-rated for general use; CSA hazardous-location certification available
Typical Applications
The 1794-OB16D is widely used in production machinery, material handling systems, packaging lines, and process control environments. Its diagnostics capability makes it especially valuable in applications requiring:
- Drive and motor contactor control
- Solenoid valve activation
- Indicator lamp management
- Fault detection and reporting in critical control circuits
- Real-time monitoring of field device health
Compatibility & Replacements
Compatible With
- Allen-Bradley CompactLogix controllers (via Flex I/O adapter modules)
- Allen-Bradley ControlLogix systems
- 1794 Flex I/O terminal base units: 1794-TB2, 1794-TB3, 1794-TB3S, 1794-TB3K, 1794-TB3SK, 1794-TBKD
- EtherNet/IP, ControlNet, DeviceNet, and Universal Remote I/O protocols
- Studio 5000 Logix Designer software for configuration and diagnostics
Replaces / Drop-In Replacement For
- 1794-OB16 (standard, non-diagnostic version)
- Earlier Series A modules with equivalent functionality
Works With
- Studio 5000 Logix Designer (RSLogix 5000)
- EtherNet/IP real-time diagnostics
- Allen-Bradley Flex I/O distributed I/O architecture
- ControlNet and DeviceNet adapter cards
- Universal Remote I/O systems for remote I/O applications
