Product Summary
The Allen-Bradley 1794-OF8IH is an isolated output HART analog module. It belongs to the Rockwell Automation Flex I/O series. This module delivers eight single-ended, isolated analog outputs. Engineers configure these outputs for 0-20 mA or 4-20 mA signals. The module provides high precision with its 16-bit unipolar resolution. It supports HART communication for smart field device integration. This module simplifies wiring with its jumperless and switchless design.
Product Procurement & Buyer Guide
Understanding the 1794-OF8IH Core Value
Procurement managers need a reliable module for process control. The 1794-OF8IH meets this need with isolated outputs. Each of the eight channels provides galvanic isolation. This isolation protects your system from ground loops. It also prevents electrical noise from corrupting signals. The module supports HART pass-through messages for smart device data. This feature allows you to access diagnostic information remotely.
Technical Specifications for Selection
You must verify compatibility with your control system. The 1794-OF8IH module uses a 16-bit digital-to-analog converter. It achieves a conversion rate of 10 milliseconds per channel. This speed ensures responsive control for your actuators. The module operates on a FlexBus current of 80 mA at 5V DC. Its maximum power dissipation is 5.0 Watts at 24V DC. The thermal dissipation reaches 17.06 BTU per hour at 24V DC.
Installation and Mounting Requirements
This module requires a compatible terminal base for installation. You must use either the 1794-TB3 or the 1794-TB3S base unit. The module locks securely when you rotate the keyswitch to position four. This mechanical keying prevents incorrect module insertion. The module is factory calibrated and requires no field adjustments. This feature reduces your setup time and eliminates calibration errors.
Data Formats and Programmability
The 1794-OF8IH supports multiple data formats for flexibility. You can program each channel independently with different ranges. The available formats include Engineering Units and Percent of Full Scale. You can also select RAW or Proportional Count formats. This flexibility allows seamless integration with various control programs. The module detects lead breakages and overrange or underrange conditions.
HART Communication Capabilities
This module provides dedicated registers for HART data processing. Each register is a six-word structure containing critical fields. The fields include Device information and HART Communication status. It also stores Loop Status and the primary value. The primary value uses IEEE 754-1985 single-precision 32-bit floating point format. The module supports one or two pass-through connections. Each connection supports eight queues for efficient data handling.
Operating Environment and Durability
The 1794-OF8IH module operates in a temperature range of 32 to 131 degrees Fahrenheit. This range suits most industrial environments. The module does not require an external power supply. It draws all necessary power directly from the FlexBus backplane. The channel settling time is 70 milliseconds for stable output signals.
Logistics & Standard Packaging Details
- One Allen-Bradley 1794-OF8IH Flex I/O Isolated Output HART Module
- Factory calibration certificate included with the module
- Installation guide for proper mounting and wiring procedures
- Compatible with 1794-TB3 or 1794-TB3S terminal bases (sold separately)
- Express delivery shipping is available via FedEx, UPS, and DHL
