Discrete Output Module Allen-Bradley 1794-OB8 8-Channel Sourcing

Product Overview

The Allen-Bradley 1794-OB8 is a Flex I/O digital DC output module. It provides eight sourcing outputs. This module operates at 24V DC nominal voltage. The outputs are not fused at the factory. You can add field fusing as needed. It works in hazardous locations in Europe and North America. The module fits into a terminal base unit. You can insert or remove it under power. This feature saves time and avoids system restart.

Application Scenarios

Use the 1794-OB8 in industrial automation systems. It connects to actuators, solenoids, indicator lights, and other DC loads. It works well in discrete manufacturing, process control, and material handling. The module suits both standard and extreme environments. The XT version offers extended temperature range. This reduces panel and maintenance costs.

Technical Specifications

• Outputs: 8, sourcing current
• On-state voltage: 24V DC nominal
• Output current rating: 4A total
• On-state current max: 500mA per channel
• On-state voltage drop max: 0.5V DC
• Off-state leakage current max: 0.5mA
• Isolation voltage: 50V continuous
• FlexBus current: 60mA at 5V DC
• Power dissipation: 3.3W at 31.2V DC max
• Thermal dissipation: 11.2 BTU/hr at 31.2V DC max
• Operating temperature: 0 to 55 °C (32 to 131 °F)
• Relative humidity: 5 to 95% noncondensing
• Output delay: 0.5ms off-to-on, 1ms on-to-off
• External power supply: 10 - 31.2V DC with 5% AC ripple, 10 - 35mA
• LED indicators: 16 yellow status LEDs
• Communication options: ControlNet, DeviceNet, EtherNet/IP, Universal Remote I/O

Installation & Maintenance Guide

Mount the module on a DIN rail by snapping it into place. Use compatible terminal bases like 1794-TB3, 1794-TB3S, or 1794-TBKD. Ensure the FlexBus connector engages properly. Wire field devices to the top terminal strip. Connect power to the middle and bottom strips. You can daisy-chain power to adjacent modules. Remove the module without powering down the system. This allows easy replacement or expansion. Check LED status indicators for channel diagnostics. Keep the module within operating temperature and humidity limits.

Packing List

• 1 x Allen-Bradley 1794-OB8 Flex I/O Digital DC Output Module
• 1 x Product documentation

Shipping is via Fedex, UPS, or DHL depending on your location.