Product Details
Product Overview
The Allen Bradley 1794-CJC2 provides the critical thermal reference required for accurate thermocouple measurements within the FLEX I/O platform. This kit consists of two high-precision Cold Junction Compensation (CJC) thermistors that plug directly into the terminal base of a thermocouple input module. It eliminates measurement errors caused by the junction of dissimilar metals at the terminal block, ensuring the PLC receives a true temperature reading. We supply this kit as 100% Brand New and Original, ensuring your process control loops maintain factory-calibrated accuracy.
Technical Specifications
The 1794-CJC2 kit utilizes specialized thermistor technology to stabilize temperature data:
| Feature | Specification |
| Manufacturer | Allen Bradley |
| Product Line | FLEX I/O (1794) |
| Compatible Families | 1794 FLEX, FLEX EX, FLEX XT |
| Module Compatibility | 1794-IRT8, 1794-IT8, 1794-IT8I |
| Sensor Type | Precision Thermistor |
| Kit Quantity | 2 Sensors per Kit |
| Operating Temp Range | -20°C to +70°C (-4°F to 158°F) |
| Relative Humidity | 5% to 95% (Non-condensing) |
| Ingress Protection | IP20 |
| Mounting | Terminal Base Integrated |
Engineering Advantages
The 1794-CJC2 kit optimizes thermal monitoring in complex distributed I/O environments:
-
Hardware-Based Error Correction: These sensors measure the exact temperature of the terminal screws where the thermocouple wires connect. This data allows the input module to mathematically subtract the ambient thermal voltage, leaving only the actual process temperature.
-
Rugged Environmental Resilience: The sensors operate reliably across an extended temperature range from -20°C to +70°C. This makes the kit suitable for remote I/O cabinets located near furnaces or in unconditioned outdoor enclosures.
-
Seamless Terminal Integration: The design allows for rapid installation into the 1794-TBN or 1794-TB3 terminal bases. The sensors seat firmly into designated slots, preventing accidental displacement during high-vibration machine operation.
-
Support for Extreme Environments: Compatibility with FLEX XT (Extended Temperature) and FLEX EX (Hazardous Location) modules ensures that critical temperature safety interlocks function correctly in the most demanding industrial sectors.
FAQs
-
How many 1794-CJC2 kits do I need for a single 8-channel module?
Each 1794-CJC2 kit contains two sensors. You require exactly one kit (two sensors) per thermocouple module. Typically, you install one sensor on each side of the terminal base to provide a balanced thermal reference for all input channels.
-
Does this kit require separate wiring to the PLC?
No. The 1794-CJC2 sensors connect directly into the dedicated terminals on the 1794 terminal base. The I/O module automatically detects the thermistor resistance through the backplane connection, requiring no additional field wiring or external power.
-
Can I use the 1794-CJC2 with other I/O brands?
No. This kit features a specific form factor and resistance curve designed exclusively for Allen Bradley FLEX I/O thermocouple modules. Using third-party sensors will result in significant temperature offset errors or module diagnostic faults.
-
What happens if a CJC sensor fails or is missing?
The thermocouple module detects the open circuit and flags a "CJC Open" fault in the controller. Without these sensors, the module cannot perform the necessary cold-junction compensation, and your temperature readings will drift significantly as the ambient temperature inside the control cabinet changes.
Additional Information
- 100% Genuine Parts: All products are original and authentic, ensuring reliable industrial performance.
- 30-Day Refund Guarantee: Return any in-stock item within 30 days in original, unopened packaging for a full refund (excluding shipping and fees).
- 12-Month Warranty: Covers defects in materials or workmanship; excludes misuse, normal wear, or unauthorized modifications.
- Worldwide Shipping: We ship via USPS, UPS, FedEx, and DHL. Delivery times vary by country and may be subject to customs or import fees.
- Support & Contact: Technical and warranty assistance is available anytime. Contact us here: Contact.
- Purchase Guidance: Check product specifications and compatibility carefully before ordering to ensure proper application.
Tech & Buying Guide
Mastering Modern Industrial Joystick Controls in Heavy Automation
Industrial joysticks play a pivotal role in human-machine interaction across heavy material handling and mobile hydraulics. These tactile controllers translate complex operator movements into precise electrical signals for PLCs, motion controllers, and DCS networks. Consequently, selecting and installing the right joystick architecture ensures operator safety, reduces fatigue, and optimizes equipment performance.
Navigating Industrial Automation Failures: Types, Causes, and Mitigation Strategies
Modern manufacturing relies heavily on automated control systems to maximize throughput and maintain product quality. However, unplanned downtime in industrial automation can cost facility operators thousands of dollars per hour. Understanding how programmable logic controllers (PLCs), distributed control systems (DCS), and field instrumentation fail empowers engineering teams to implement robust preventive maintenance strategies.
Essential Motion Control Commands: A Practical Guide for Engineers
Automation engineers often rely on precise position and speed control to drive modern factory machinery. Modern industrial systems, such as Programmable Logic Controllers (PLCs) and Distributed Control Systems (DCS), depend heavily on standardized motion instructions. Mastering these commands ensures operational safety, protects mechanical components, and optimizes cycle times across production lines.