Several points to note when choosing a process verifier

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The process calibrator has a very rich set of output and measurement functions; it can generate DC voltage, DC current, resistance, as well as analog signals and frequency signals from various types of thermocouples and thermal resistors. It can measure DC voltage, DC current, output signals from thermocouples and thermal resistors, frequency signals, and more. Due to its high precision, the process calibrator can replace DC potentiometers, standard resistance boxes, standard DC voltmeters, and DC ammeters. A process calibrator combines the functions of a signal source and a standard gauge, and can be used conveniently to calibrate various instruments such as temperature transmitters and digital displays. It can also be used, in conjunction with pressure modules, to calibrate pressure and differential pressure transmitters ； Wiring is very simple during calibration; in an environment without a 24VDC power supply, the 24VDC circuit power of the process calibrator can be used to power the transmitter. When using a process calibrator to adjust various instruments, its calibration principle is the same as that of the traditional calibration methods mentioned above. As long as one is familiar with the various operating methods of the process calibrator, it is possible to calibrate the instrument. The usage instructions for the process calibrator can be found by searching for the technical article “Process Calibrator Usage Guide” on Baidu. In the daily work of instrument technicians, process calibrators are just like digital multimeters – tools that need to be carried around at all times. A tool that is easy to use is essential for instrument technicians! It is such rigid demands that have led to the emergence of countless brand of process calibrators in the domestic market, which also confuses instrument technicians: which type of process calibrator should be chosen to calibrate instruments? Before answering this question, the author would like to share with you the technical requirements for the standard instruments needed for calibration as specified in the JJF1664-2017 calibration specification for temperature display instruments: ◆ DC resistance box: Purpose – to simulate the output of thermal resistors; Accuracy grade – not lower than 0.02 grade; Measurement range – 18Ω–450Ω. ◆ Standard DC voltage source or low-potential DC potentiometer: Purpose – to simulate the output of thermocouples; Accuracy grade – not lower than 0.05 grade; Measurement range – 0–80mV. ◆ Standard signal source: Purpose – to serve as a standard signal source for secondary instruments that receive signals during calibration; Accuracy grade – not lower than 0.02 grade; DC voltage: 0–10V; DC current: 0–22mA. Why is it necessary to introduce the details of these standards? This is because the process calibrator incorporates the functions of a DC resistance box, a standard DC voltage source or low-potential DC potentiometer, and a standard signal source. It is obvious that the accuracy requirements of the process calibrator must meet the technical specifications set by the standards in order to satisfy the needs of instrument technicians when calibrating instruments. Therefore, when choosing a process calibrator, instrument technicians must consider accuracy, stability, and temperature drift as the three key technical indicators for evaluating the performance of such calibrators! Many process calibrators may appear to have acceptable accuracy specifications on the surface, but they suffer from poor stability and significant temperature drift. Using such calibrators to adjust instruments will inevitably result in large measurement errors; as the saying goes, a small error can lead to huge discrepancies. Choosing a suitable tool can greatly help reduce the workload associated with instrument maintenance. If you have doubts about which type of calibrator to use for adjusting instruments, feel free to call 0871-65127691 or seek professional technical guidance through the website’s customer service. Method of calibrating instruments using a process verification instrument http://yunrun.com.cn/tech/2466.html