I. Overview The TCDR-300 Thermal Conductivity Meter is a new dual-plate testing device designed according to GB10294-2008, "Determination of Steady-State Thermal Resistance and Related Properties of Thermal Insulation Materials—Guarded Hot-Plate Method." It is specifically used to measure the thermal conductivity of various homogeneous plate-shaped insulation materials as well as non-conductive thermal materials. Equipped with an advanced microcomputer-based automatic control system, this instrument boasts high levels of intelligence, making it the ideal choice for conducting such testing projects in China today. II. Testing Applications This meter is designed to measure the thermal conductivity of diverse homogeneous plate-shaped insulation materials and non-conductive thermal materials. III. Measurement Principle Under steady-state conditions, a one-dimensional, constant heat flow similar to that found in an infinitely large plate bounded by two parallel isothermal plates is established within the central measurement area of the guarded hot-plate apparatus, passing through a uniform plate-shaped specimen with parallel surfaces. IV. Applicable Standards This instrument complies with GB10294-2008, "Determination of Steady-State Thermal Resistance and Related Properties of Thermal Insulation Materials—Guarded Hot-Plate Method." V. Technical Specifications 1. Model: TCDR-300 2. Overall Dimensions: 1030 × 800 × 1500 mm 3. Specimen Size: Measurement area 150 × 150 mm, Guard area 300 × 300 mm 4. Specimen Thickness: ≤60 mm 5. Thermal Conductivity Range: 0.01–2 W/(m·K) 6. Cold Plate Temperature: 5°C–90°C 7. Hot Plate Temperature: ≤120°C 8. Measurement Accuracy: ≤3% 9. Test Repeatability: ≤1% 10. Power Supply: 3 kW, 220 V VI. Instrument Structure The device employs the dual-specimen guarded hot-plate method (as per GB10294-2008) and consists of several key components, including a microcomputer-based automatic control system, a measurement heating unit, a cold plate unit, a guard unit, an external protective unit, a measurement system, a clamping system, and a refrigeration mechanism. 1. Microcomputer-Based Automatic Control System: The computer outputs signals that are processed via I/O and D/A conversion to precisely control actuators, enabling functions such as temperature regulation, data calculation, temperature acquisition, test report printing, and real-time process curve display. The user-friendly interface displays temperature readings from all relevant surfaces and includes a self-diagnostic feature. 2. Measurement Heating Unit: This unit features an aluminum heating panel, renowned for its exceptional thermal conductivity. This design ensures more uniform heating across the plate surface while minimizing thermal inertia, resulting in highly accurate measurement outcomes. 3. Cold Plate Unit: Two cold plates are maintained at a constant temperature using a thermostatic water bath. Temperature settings are managed automatically by the microcomputer, effectively minimizing temperature differences between the two plates and ensuring consistent test conditions. 4. Guard Unit: Made from the same material as the measurement heating unit, this component precisely controls temperature gradients across the sealing gap, significantly reducing measurement errors. 5. External Protective Unit: A protective sleeve made of cork material is employed to stabilize environmental conditions during testing, thereby enhancing the accuracy and reliability of results. 6. Measurement System: Highly stable digital temperature sensors from Dallas Semiconductor’s DS18B20 series, combined with precision DC power sensors, ensure highly accurate data collection and analysis. 7. Clamping System: Utilizing pneumatic technology, the system automatically applies controlled pressure to securely clamp the specimen in place, eliminating the need for manual adjustments and ensuring convenient and reliable specimen installation. 8. Refrigeration Mechanism: This feature enables rapid cooling of the cold plates and maintains the average specimen temperature below ambient levels, expanding the instrument’s operational range while minimizing sensitivity to external environmental factors. VII. Operating Instructions 1. Manual Operation: - After powering on, press the "Coefficient Start" button on the control cabinet. Once activated, the indicator light will turn green. To open or close the specimen clamping mechanism for easy installation or removal, simply tap either the "Cold Plate Release" or "Cold Plate Tighten" buttons. 2. Microcomputer-Controlled Operation: - Connect the microcomputer system to the power supply, start the computer, and double-click the thermal conductivity icon to access the main interface. - Set relevant parameters based on the specific test requirements, including test number, specimen number, test date, specimen area, specimen thickness, measurement plate temperature, guard plate temperature, and cold plate temperature. Note that after entering each parameter, press the Enter key to confirm; a prompt window will appear upon successful setup. - Under the "System" menu, select "Sensor" to verify that all sensors are functioning properly. - Access the "Debug" option under the "System" menu to enter the debugging interface. - Click "Start" under the "Test" menu to initiate the testing process. - If the cold plate temperature exceeds (ambient temperature + 10°C), press the "Water Cooling Stop" button. Unless otherwise specified, default settings remain unchanged from factory calibration; any deviations must be confirmed by on-site service personnel. - From the main screen, select "Sample Record" under the "Test" menu to view detailed experimental data throughout the entire process. Historical data can also be deleted as needed. - Use the "Test Record" option under the "Test" menu to access the final experimental log, which can then be printed by clicking "Print." - The test will automatically conclude once completed. If you need to halt the experiment prematurely, click "End" under the "Test" menu on the main screen to exit the testing mode. - Finally, select "Exit" under the "System" menu on the main screen to safely shut down the system and disconnect the power supply. - After completing the test, carefully remove the specimen and disconnect the power supply to finalize the experiment. - Lastly, prepare and organize the experimental report for documentation purposes. VIII. Precautions 1. After each experiment, pay special attention to cleaning and performing regular rust-prevention maintenance to ensure the longevity and optimal performance of the equipment.2. After the equipment is installed and debugged, operators should regularly check whether the grounding protection of the control box is functioning properly. 3. The environment and equipment should be kept thoroughly clean, with the ambient temperature maintained between 18°C and 25°C and relative humidity below 50%. 4. Ensure that the antifreeze solution or water in the tank remains clean, and replace the antifreeze or water periodically. 5. Regularly verify the power sensor readings. 6. When the entire machine is left unused for an extended period, disconnect the main power plug and take precautions against rust and dust. Any changes will be subject to service personnel training—no further notice will be provided.