Introduction 
       Thermal conductivity is an important parameter for the assessment of the heat transfer property of materials. The thermal conductivity measurement instrument based on GHP is an absolute method especially designed for the assessment of the heat transfer property of thermal insulation materials, which are widely used in the all kinds of buildings, including civil buildings and industrial buildings, as well as many other fields, such as cold chain transportation, aerospace, and oil and natural gas industries, etc..
       The DD300F serials thermal conductivity measurement instrument based on GHP has a single specimen design, which is in accordance with the ISO 8302 and GB/T 10294. This DD300F series have a robust mechanical structure, excellent thermal insulation design, an advanced electronic controller based on micro-chips and surface mounted devices (SMD) ,  user-friendly software with graphical interface and intelligent self-calibration property. 
        Compared with D300FX series, the DD300F series have the added benefits of automatic fastening of the specimens and the automatic detection of the specimen thickness.

Properties
       ① in accordance with ISO 8302 and GB/T 10294-2008
       ② self-designed electronics based upon the most advanced micro-chips and surface mounted devices(SMD) instead of traditional industrial meters. 
       ③ PID based self-tunning function assuring the accuracy of the controlled temperature.
       ④ the heat transfer between the hot and guard plates approaches to zero by internal accurate mathematical models and the intelligent calibration method.                
       ⑤ the test data fits well in the whole temperature range when the SRM(standard reference materials) are tested.      
       ⑥ test results at the same averaged temperatures between the hot and cold plates but different hot and cold plates temperature differences are within the specified accuracy range. 
       ⑦ applicable to plate specimens as well as powder/grain specimens.
       ⑧  test results on specimens with different thickness of the same materials are within the specified accuracy range.
       ⑨ user-friendly software with graphical interface and intelligent self-calibration property. 
       ⑩ very short test time of around 60 minutes achieved by the algorithm of automatic self-determination of whether the steady-state is achieved or not.
 
Specifications 
       Power supply：AC 220V±5%, 1.0～2.0kW 
       Thermal conductivity measurement：
              range: 0.001～2.2 W/(m·K)
              repeatability: ±1.0%                                                                             accuracy: ±2.5%
       Temp. measurement:
              range:
                     DD300F-D0: cold plate: 0～95℃，hot plate: 30～99.9℃
                     DD300F-D15: cold plate: -15～95℃，hot plate: 10～99.9℃
                     DD300F-D30: cold plate: -30～95℃，hot plate: -10～99.9℃
              resolution: 0.01℃                                                                              accuracy: ±0.1℃
       Specimen thickness measurement:
             resolution: 0.05 mm                                                                           repeatability: 0.1mm       
       Test time: about 60 minutes
       Environment: 　 
              room temp.: 22±3℃                                                                          humidity: 20～60%RH 
       Specimens: 
              lateral dimensions: 300mm×300mm                                                 thickness: 5～50  mm 
              planeness: <0.5mm 
‍       Size of the test platform: 510×600×1500mm     
       Weight: 80kg