Product Overview
When precise temperature monitoring is critical in harsh industrial environments, the Allen-Bradley 1794-IR8 Flex I/O RTD Module delivers reliable performance. This 8-channel Resistance Temperature Detector (RTD) input module converts analog temperature signals into digital data with 16-bit resolution across 435 ohms. Designed for the Flex I/O platform, the 1794-IR8 supports a wide range of RTD sensors, making it a versatile choice for process control and monitoring applications.
Technical Specifications
The Allen-Bradley 1794-IR8 offers a robust set of specifications that ensure accurate and stable temperature readings:
-
Number of Inputs: 8 channels
-
Nominal Input Range: 1 to 433 ohms
-
Resolution: 16 bits across 435 ohms
-
RTD Excitation Current: 718.36 µA
-
Accuracy: 0.05% full scale (max) in normal mode; 0.01% full scale (typical) in enhanced mode (without calibration, at low humidity)
-
Data Format: 16-bit 2's complement or offset binary (unipolar)
-
System Throughput: Normal mode: programmable from 28 ms to 325 ms per channel (default 325 ms for 1 channel, 2.6 s for 8 channels); Enhanced mode: programmable from 56 ms to 650 ms per channel (default 650 ms for 1 channel, 2.925 s for 8 channels)
-
Normal Mode Noise Rejection: -60 dB at 60 Hz
-
Channel Bandwidth: 0 to 2.62 Hz
-
Isolation Voltage: 850 V DC
-
Power Dissipation: 3 W at 31.2 V DC maximum
-
Thermal Dissipation: 10.2 BTU/hour at 31.2 V DC maximum
-
FlexBus Current: 20 mA
-
Operating Temperature: 0 to 55 °C (32 to 131 °F)
-
Storage Temperature: -40 to 85 °C (-40 to 185 °F)
-
Vibration: 5 g @ 10 to 500 Hz
-
Operating Shock: 30 g
-
Mounting: DIN Rail
Industry Applications
The Allen-Bradley 1794-IR8 excels in applications where accurate temperature measurement is essential. Common use cases include:
-
Process Industries: Monitor reactor temperatures in chemical plants, ensuring safe and consistent production.
-
HVAC Systems: Track duct and ambient temperatures in large commercial buildings to optimize energy usage.
-
Food & Beverage: Verify pasteurization and sterilization temperatures to maintain product quality and safety.
By choosing the 1794-IR8, you gain a module that simplifies integration and reduces wiring complexity, ultimately lowering installation costs and downtime.
Installation & Setup Guidance
Mount the Allen-Bradley 1794-IR8 on a standard DIN rail. The module requires a compatible terminal base, such as the 1794-TB2, 1794-TB3, or 1794-TB3T. Wire size is determined by the installed terminal base. Ensure proper grounding and follow the manufacturer's guidelines for RTD sensor connections. The module supports a variety of RTD types, including platinum, nickel, and copper sensors, so verify the sensor's alpha coefficient and temperature range before wiring.
Maintenance & Reliability
Regular inspection of the 1794-IR8 ensures long-term reliability. Check for loose connections and signs of corrosion on the terminal base. Keep the module within its specified operating temperature range to avoid thermal stress. The module's robust design, with 30 g shock tolerance and 5 g vibration resistance, makes it suitable for demanding environments. By implementing a routine maintenance schedule, you can maximize uptime and extend the service life of your investment.
Compatibility & Integration
The 1794-IR8 is part of the Allen-Bradley Flex I/O family, designed to work seamlessly with Rockwell Automation controllers. It communicates via the FlexBus backplane, requiring a FlexBus current of 20 mA. The module is compatible with a range of terminal bases, providing flexibility in system design. For seamless integration, ensure your controller supports the Flex I/O adapter.
Selection Guide & Purchasing Advice
Before purchasing the Allen-Bradley 1794-IR8, verify that your system's power supply can deliver the required voltage (24 V DC nominal, 19.2 to 31.2 V DC) and that the terminal base is compatible. Consider the number of channels needed and the sensor types you will use. PLC Source PRO is a trusted supplier of genuine industrial automation parts, offering reliable sourcing and prompt delivery. Contact our team to confirm availability and ensure the 1794-IR8 meets your application requirements.