1 overview

The ARS8051C 6.0 version thermal automatic calibration system is one of the new fourth generation thermal automatic calibration products developed by our factory at the beginning of the new century. It is a new generation product developed entirely in the Windows environment using the language of the Windows environment. The system is centered around a high-end microcomputer, equipped with a high-precision imported digital multimeter, as well as a measurement and control system consisting of a low potential scanning switch, power regulator, and other components. The operator can operate in ChineseＷin95/Ｗin98/WinMeThe entire process can be conveniently operated with a mouse under the operating system, and the microcomputer system displays real-time temperature control curves, temperatures, and calibration time parameters of the calibration furnace (or oil tank, water tank, etc.). The system fully processes data in accordance with the current national metrological verification regulations, and can print various record forms and verification certificates. It can also retain original records for future reference. The system has fully automated the calibration process of thermocouples and thermal resistors, including automatic temperature control, automatic calibration, automatic data processing, and automatic printing of calibration results. Greatly reducing the labor intensity of operators and improving the quality of calibration work. This device also provides authentication programs and data file management programs for the system, providing convenience for operators to archive, retrieve, and query the authentication and verification results of the system.

2 Thermal automatic calibration systemMain performance characteristics

2.1 Advanced operating methodsUsing Windows software programming, completely inWin95/Ｗin98/WinMeRun on the operating platform. Fully in line with the operating habits of the Windows environment, the window interface, drop-down menu, and the use of the mouse to select input parameters and perform process operations are powerful, easy to use, flexible, and fast.

2.2 High degree of automationThe verification process involves continuous automatic temperature control, automatic verification, automatic data processing, and automatic printing of various verification records and certificates.

2.3 High precision, high resolutionSelect advanced six and a half digit high-precision imported numerical table. Accuracy of 0.005% and resolution of 0.1 μ V; 0.1m Ω. During the detection process, further digital filtering and elimination of bad values are applied to the sampled data.

2.4 Display intuitivelyDuring the verification process, the monitor displays in real-time the temperature change curve of the verification furnace (or oil tank, water tank, etc.), the temperature of the verification furnace (oil tank, water tank), the temperature of the verification point, the verification process, the cold end temperature, the millivolt value of the temperature control thermocouple (resistance value of the temperature control thermistor), and the verification time.

2.5 Fully functional and flexible configuration

Can verify various grades of low-cost metal thermocouples and grade II precious metal thermocouples, as well as various grades of thermal resistors

Can verify two-wire (four wire) and three wire heating resistors

Multiple batches of calibration can be performed on the thermistor at the same temperature point; It can calibrate 0 ℃ and 100 ℃ points at different times, and the program automatically compiles and synthesizes reports, which is more in line with the actual situation of thermal resistance calibration and can effectively improve work efficiency

It has multiple cold end compensation methods. Equipped with zero point, input room temperature, and automatic tracking compensation for cold end for operators to choose from

Correction can be made to the compensation wire to make the calibration results more accurate

The temperature point can be set arbitrarily. Thermocouples operate between 300 ℃ and 1200 ℃, with intervals of 5 ℃; Hot spot resistance can be set arbitrarily every 10 ℃ between 50 ℃ and 300 ℃

Low temperature thermocouples (50 ℃ -300 ℃) can be used to calibrate work in oil tanks

There are interface drivers with multiple number tables available, allowing operators to freely select from the menu, increasing the flexibility of system configuration

Equipped with manual/automatic switching function, providing means of operation in special circumstances

The main control box is fully operated with buttons, making it more convenient and accurate to operate

2.6 High temperature control accuracy and short calibration timeAdopting multiple optimized direct digital control algorithms and providing multiple sets of temperature control parameter selections for different objects. Ensure that the temperature change rate during the verification process is less than 0.2 ℃/min for the verification furnace; The oil tank temperature is less than 0.04 ℃/10min. Thermocouples generally have a calibration time of about 30 minutes for each calibration point; And the thermal resistance takes about 60 minutes.

2.7 High degree of standardization and standardized reportingThe verification process, data processing, verification records, and verification certificates of thermocouples and thermal resistors fully comply with the national metrological verification regulations JJG-351-96; Requirements of JJG-229-98 regulations and 90 temperature scale promotion manual. Especially, the verification procedure for thermal resistance has been reorganized in accordance with the latest JJG-229-98 regulations issued by the country.

2.8 Equipped with system authentication testing functionThe system is equipped with a certification testing module for thermocouples and thermal resistance calibration devices, which can automatically verify the total uncertainty, repeatability error, and temperature field of the calibration furnace and oil tank for thermocouples and thermal resistance calibration devices, and compile and print certification reports. It brings great convenience to the operator for system standardization and system review.

2.9 Data management functionThe system is equipped with data file management function, which can store, archive, retrieve and query calibration reports. The operator can access or print any calibration record report or calibration certificate at any time. The device processes the preview and printing of the report in the spreadsheet "Excel" under "Office 97 (2000)". Due to the powerful features and convenient and flexible operation methods of Excel, previewing and printing reports are more user-friendly.

2.10 Improved protection measuresEquipped with a system self-test program, it can perform self-test on digital meters, main control boxes, thyristor power regulators, dedicated interface cards, and wire connections. When there is a situation of overheating, thermocouple breakage, or thermocouple short circuit, the system will automatically turn off the thyristor power regulator, cut off the heating current, and prompt an alarm. When the main control box or microcomputer crashes, the system will automatically turn off the thyristor power regulator and cut off the heating current.

2.11 Reasonable hardware design and advanced manufacturing technologyAll key components are imported and undergo strict aging and inspection before leaving the factory. The thyristor power regulator can provide three power regulation outputs, providing convenience for operators to switch between different temperature controlled objects. The main control box is equipped with a CPU with a watchdog, making the system safer and more reliable.

3Main technical indicators of thermal automatic calibration system

3.1Scanning switch parasitic potential≤0.4μV

3.2 Resolution

Maximum potential measurement resolution0.1μV

Maximum resistance measurement resolution0.1mΩ

3.3　accuracy

Uncertainty in potential measurement≤0.01%

Uncertainty in resistance measurement≤0.01％

Uncertainty in thermocouple calibration≤ 1.2 ℃ (including annual variation of 0.7 ℃ for second-class standard thermocouples)

Uncertainty in thermal resistance calibration≤0.05℃

3.4 Stability of constant temperature

Thermocouple calibration process after constant temperatureFurnace temperature variation ≤ 0.2 ℃/min

Thermal resistance calibration process after constant temperatureOil tank temperature change ≤ 0.04 ℃/10min

3.5 Cold end automatic compensationWhen the cold end temperature is within the range of (20 ± 10) ℃, the compensation error is ≤ 0.2 ℃

3.6 Verification temperatureThermocouple 300-1100 ℃

Thermal resistance 0-300 ℃ (including low-temperature thermocouples)

3.7 Verification quantityThermocouples can simultaneously calibrate 1-10 units

Thermoelectric resistors can be tested simultaneously for 1 to 10 units, and multiple batches of testing are allowed at the same temperature point.

3.8 One continuous calibration point4 thermocouples

3 thermal resistors

3.9 Verification timeThermocouple calibration, under normal conditions, takes an average of about 30 minutes per hundred degrees.

3.10 This verification system processes data in accordance with the current national metrological verification regulations.

3.11 work environment: Environmental temperature 20 ℃± 3 ℃

Relative humidity ≤ 75%

3.12 Use power supplyAC 220V ± 10% 50 ± 1Hz