Overview
The Allen-Bradley 1794-OB16P /A is a FLEX I/O discrete output module designed for 24VDC control applications. This unit provides 16 electronically fused current-sourcing output channels, making it ideal for energizing solenoids, relay coils, indicator lights, and other 24VDC field devices in distributed automation systems. Each channel delivers 500 mA nominal per-channel output with an 8.0A total module current rating.
Key Features
- 16 discrete 24VDC sourcing outputs with per-channel electronic fusing protection
- Electronically fused – the “P” designation indicates internal protection (vs. unfused 1794-OB16)
- Output range: 1.0 mA to 500 mA per channel; 8.0A module total
- Surge capacity: 2A for 50 ms, repeatable every 2 seconds per channel
- Ultra-low output delay: 0.5 ms (OFF→ON), 1 ms (ON→OFF)
- Flexible supply voltage range: 10–31.2V DC (nominal 24V)
- DIN-rail mount with compatible terminal bases (TB2, TB3, TB3S, TB3K, TB3SK)
- FlexBus powered via Flex I/O connector; 60 mA @ 5V DC draw; 5.0W max dissipation @ 31.2V DC
- Operating temperature: 0–55°C; storage –40–85°C
- Certifications: UL, CSA, CE, C-TICK, KC, GOST, MARINE compliance
Technical Specifications
| Output Type | 16 × 24VDC Sourcing (Current Source) |
| Output Current (Nominal) | 500 mA per channel; 8.0A module total |
| Output Current (Min–Max) | 1.0 mA to 500 mA per channel |
| On-State Voltage (Nominal) | 24V DC |
| On-State Voltage Range | 10–31.2V DC |
| On-State Voltage Drop | 0.5V DC (max) |
| Off-State Leakage Current | 0.5 mA (max) |
| Surge Current | 2A for 50 ms, repeatable every 2 seconds |
| Output Signal Delay | 0.5 ms (OFF→ON); 1.0 ms (ON→OFF) |
| FlexBus Current | 60 mA @ 5V DC |
| Power Dissipation (Max) | 5.0W @ 31.2V DC |
| Thermal Dissipation | 17.0 BTU/hr @ 31.2V DC |
| Operating Temperature | 0–55°C (32–131°F) |
| Storage Temperature | −40–85°C |
| Relative Humidity | 5–95% non-condensing |
| Operating Vibration | 30g; 5g @ 10–500 Hz |
| Mounting | DIN Rail / Panel (requires terminal base) |
| Enclosure | Open-style (IP20) |
| Certifications | UL, CSA, CE, C-TICK, KC, GOST, MARINE |
| Terminal Connection | Screw terminal (via terminal base) |
| Compatible Models | Flex I/O systems with 1794 architecture; works with PLC5, SLC500, Logix controllers via appropriate adapters |
Typical Applications
- Manufacturing and assembly line equipment control
- Discrete process control and automation
- Energizing solenoids, proportional valve coils, and relay circuits
- Indicator lamp and signal tower control
- Distributed I/O architectures for remote or cabinet-mounted control
- Motion control and machinery sequencing
- In-cabinet and panel-mount industrial environments
Compatibility & Replacements
Compatible With
- Allen-Bradley / Rockwell FLEX I/O distributed I/O systems
- CompactLogix, ControlLogix, and PLC5 platforms (via appropriate adapters and bridges)
- Studio 5000 / RSLinx communication software
- ControlNet and EtherNet/IP communication adapters for FLEX I/O
- All 1794 FLEX I/O terminal bases (TB2, TB3, TB3S, TB3K, TB3SK)
- Standard 24V DC control power supplies and field device networks
Replaces / Drop-In Replacement For
- Other tested or worn 1794-OB16P /A modules in existing FLEX I/O configurations
- Original equipment manufacturer (OEM) direct stock replacement
- Note: The 1794-OB16P (with electronic fusing) is not a direct replacement for the 1794-OB16 (unfused) without application review; consult system documentation before substitution.
Works With
- Allen-Bradley Studio 5000 Logix Designer software
- RSLogix 5000 (legacy Logix platforms)
- EtherNet/IP and ControlNet communication protocols (via FLEX I/O adapters)
- CompactLogix and ControlLogix processors with FLEX I/O bridges
- Third-party SCADA and HMI systems supporting Logix communication
- PLC5 and SLC500 legacy systems with appropriate FLEX I/O gateways
