SPECIFICATIONS
Part No.: IS200DTTCH1AAA
Manufacturer: General Electric
Country of Manufacture: United States of America (USA)
Number of Channels: 12
Thermocouple types: E, J, K, S, T
Span: -8 mV to +45 mV
Cold junction temperature accuracy: 2 oF
Product Type: Simplex Thermocouple Input Board
Availability: In Stock
Series: Mark VI
Functional Description
IS200DTTCH1AAA is a Simplex Thermocouple Input Board developed by GE. It is a part of the Mark VI control system. The board is a compact terminal board specifically designed for DIN-rail mounting, offering convenience and space-saving benefits. With a focus on thermocouple inputs, the board provides 12 thermocouple input channels and seamlessly connects to the VTCC thermocouple processor board using a single 37-pin cable. Notably, this cable shares identical specifications with the larger TBTC terminal board, ensuring compatibility and ease of integration.
Features
- Signal Conditioning and Cold Junction Reference: Features onboard signal conditioning and cold junction reference mechanisms identical to those found on the TBTC board. These components ensure accurate signal processing and temperature measurement, maintaining consistency and reliability across the system.
- Identification Chip: An onboard ID chip is integrated to identify the board to the VTCC for system diagnostic purposes. This chip enhances diagnostic capabilities, enabling efficient troubleshooting and maintenance procedures.
- Expansion Capabilities: Two boards can be connected to the VTCC, effectively doubling the total number of thermocouple inputs to 24. This expansion capability offers flexibility and scalability, accommodating a wide range of applications and requirements.
- Terminal Block Configuration: High-density Euro-Block type terminal blocks are permanently mounted, providing robust and reliable connections. Each terminal block features two screw connections for the ground connection (SCOM), ensuring secure grounding. Additionally, every third screw connection is designated for the shield, further enhancing signal integrity and noise reduction.
- Vertical Stacking: To optimize cabinet space utilization, the boards can be stacked vertically on the DIN-rail. This stacking capability conserves valuable cabinet space, allowing for efficient organization and layout of control system components.
- Compatibility Note: It's important to note that only the Simplex version is available. Additionally, the DTTC board is not compatible with the PTCC I/O pack, ensuring compatibility and system integrity.
Cold Junction Compensation
- Cold junction compensation is vital for ensuring accurate temperature measurements from thermocouples. This compensation process involves measuring the reference junction temperature at a specific location on the DTTC board, which serves as a benchmark for adjusting temperature readings.
- By comparing the reference junction temperature with the actual measurement points, any temperature differentials can be accounted for, ensuring precise and reliable temperature readings across the system.
Cold Junction Temperature Accuracy
- The accuracy of the cold junction temperature measurement is paramount for maintaining precision in temperature readings. The DTTC board provides a high level of accuracy, with a cold junction accuracy of 2oF.
- This level of accuracy is crucial for ensuring that temperature measurements remain reliable and consistent, even in demanding industrial environments where fluctuations in temperature can occur. With such precise cold junction compensation, the board ensures that temperature readings are accurate and trustworthy, meeting the stringent requirements of industrial applications.
Board Fault Detection
- Regular Hardware Limit Checks: The system conducts regular hardware limit checks to monitor input signals and detect any deviations from preset high and low levels. These checks are performed systematically and continuously to ensure comprehensive coverage and timely identification of potential faults.
- Identification of Limit Exceedance: When a limit is exceeded, indicating a potential fault or anomaly in the input signal, the system immediately triggers a logic signal. This signal serves as an alert, signaling to the system's monitoring and control mechanisms that an abnormal condition has been detected.
- Prevention of Erroneous Data Processing: In response to the triggered logic signal, the affected input is promptly flagged, and its scanning process is halted. By preventing further scanning of the affected input, the system ensures that erroneous or inaccurate data is not processed or incorporated into subsequent calculations or actions.
- Mitigation of Potential Risks: By halting the scanning of the affected input upon detection of a fault, the system effectively mitigates potential risks associated with erroneous data. This proactive approach helps maintain the integrity of the system's output and prevents cascading errors that could compromise overall performance.
- Continuous Monitoring and Adaptation: Fault detection is not a one-time event but rather an ongoing process embedded within the system's operational framework. Continuous monitoring and adaptation allow the system to dynamically respond to changing conditions and evolving fault scenarios, ensuring consistent performance and reliability over time.
ID Chip Check
- Each terminal board cable is equipped with an ID chip located on the J3 connector.
- The VTCC interrogates this ID chip to verify the identity of the terminal board. By cross-referencing the information stored on the ID chip with the expected values, the VTCC can detect any mismatches, indicating a potential hardware incompatibility. This check enhances system reliability and ensures proper integration of components.
The WOC team is always available to help you with your Mark VI requirements. For more information, please contact WOC.
Frequently Asked Questions
What is IS200DTTCH1AAA?
It is a simplex thermocouple input board developed by GE under the Mark VI series.
How are hardware limits checked for thermocouple inputs on the board?
Each thermocouple type has hardware limit checking based on preset high and low levels set near the ends of the operating range. If the VTCC detects that these limits are exceeded, a logic signal is triggered, and the input is no longer scanned. Any instance of input hardware limits being exceeded results in a composite diagnostic alarm, L3DIAG VTCC, referring to the entire board.
How does the VTCC identify individual terminal boards?
Each terminal board cable is equipped with its own ID device, which is interrogated. The ID device contains information such as the terminal board serial number, board type, and revision number. If the VTCC encounters a mismatch between the ID device information and the expected values, a hardware incompatibility fault is generated.
What is the purpose of injecting a small current into each thermocouple path when operating with the I/O processor?
When operating with the I/O processor, a small current is injected into each thermocouple path. This current serves the purpose of detecting open circuits. Additionally, the injected current is of a polarity that would create a high-temperature reading should a thermocouple open, allowing for timely detection and alerting of potential issues.
