Allen-Bradley 1794-OB8 | Flex I/O Digital DC Output Module

Overview

The 1794-OB8 from Allen-Bradley is a Flex I/O digital DC output module with eight sourcing outputs. It efficiently connects field devices to the I/O bus, supporting versatile industrial automation tasks.

Electrical Specifications

This module delivers a nominal 24V DC on-state voltage with a maximum current of 500 mA per channel. The on-state voltage drop is 0.5V DC, while the off-state leakage current is limited to 0.5 mA. It features 50V continuous isolation and a Flexbus current of 60 mA at 5V DC. Maximum power dissipation is 3.3W at 31.2V DC, producing 11.2 BTU/hr thermal dissipation.

Connectivity and Mounting

The 1794-OB8 easily snaps onto a DIN rail and connects with compatible terminal bases, including 1794-TB3, 1794-TB3S, and 1794-TBKD. It supports communication over ControlNet, DeviceNet, EtherNet/IP, and Universal Remote I/O networks. The module features 16 yellow LED indicators to display channel status.

Performance and Compatibility

The 1794-OB8 offers 0.5ms off-to-on delay and 1ms on-to-off delay, enabling fast and accurate output switching. External power ranges from 10–31.2V DC with 5% ripple, and the module accommodates 10–35 mA of current. XT versions provide operation in extreme environments, reducing panel maintenance costs.

Environmental Ratings

This module operates reliably within 0–55°C (32–131°F) and 5–95% non-condensing humidity, ensuring stable performance in industrial settings.

Applications

The 1794-OB8 is ideal for automation, machine control, and remote I/O systems, offering reliable, high-speed output control for a wide variety of industrial devices.