Pressure sensor (static) calibration

Pressure sensors (static) are an important type of sensor, and the following is a detailed overview of them:

1、 Definition and Principle
Definition: Pressure sensor (static) refers to the output signal of the sensor under no pressure, also known as zero drift. It is an important indicator used to calibrate and detect the accuracy and stability of sensors.
Principle: Static pressure sensors often use metal or semiconductor strain gauges. When subjected to external pressure, the strain gauge undergoes deformation, thereby changing its resistance value. By measuring the change in resistance value, the magnitude of the force can be calculated, achieving pressure monitoring.

IIPressure sensor (static) calibrationprepare
Equipment preparation: Ensure that the calibrated pressure sensor is complete and visually undamaged, and that all components are securely assembled.

Pressure sensor: Ensure that the calibrated pressure sensor is complete and visually undamaged, and that all components are securely assembled.

Pressure standard: Select a pressure standard whose absolute value of the basic error should be less than one-third of the absolute value of the basic error of the tested pressure sensor.

Incentive power supply: It should be matched according to the requirements of the pressure sensor, and the stability should be 1/5~1/10 of the absolute value of the allowable basic error of the tested pressure sensor.

Reading recording device: The absolute value of the basic error should be less than 1/5~1/10 of the allowable absolute value of the basic error of the tested pressure sensor. Digital voltmeters, digital frequency meters, ammeters, etc. can be used.
Other equipment: vacuum gauge, digital barometer (or standard barometer), thermometer, hygrometer, precision resistance box, etc.

Environmental conditions:
The ambient temperature during calibration depends on the accuracy level of the pressure sensor being tested. For example, levels 0.01 and 0.02 are 20 ± 1 ℃, levels 0.05 are 20 ± 2 ℃, and levels 0.1, 0.2, and 0.5 are other specified temperatures.
Before calibration, the pressure sensor should be placed at the calibration ambient temperature for more than 2 hours.
The relative humidity should be less than 80%, and the atmospheric pressure should be between 86 and 106 kPa.

IIIPressure sensor (static) calibrationstep
Installation and Connection:
Install the pressure sensor on the pressure standard including the pressurization (or evacuation) device as required.
The pressure sensor, excitation power supply, reading recording device and other instruments and equipment should be connected and adjusted according to the prescribed circuit to ensure that they are in normal working position and state.
System preheating and inspection:
After the verification system is correctly installed and connected, preheat for half an hour.
Pressurize the calibration system to the upper measurement limit (or evacuate it to the lower measurement limit), stabilize the pressure for 1 minute, and then slowly open the atmosphere for 3 consecutive times. When maintaining constant pressure, observe the reading of the reading device and check the sealing of the pipeline system.
Selection of verification points:
For pressure sensors with an accuracy level below 0.1 (including 0.1), at least 6 calibration points (including zero) should be uniformly or reasonably selected within the measurement range.
For pressure sensors with an accuracy level higher than 0.05 (including 0.05), at least 9 calibration points (including zero) should be uniformly or reasonably selected within the measurement range.
Calibration and recording:
Generate a significant fluctuation in the input pressure at the measurement upper limit (or lower limit), and record the pressure sensor reverse stroke output value at the measurement upper limit (or lower limit) after the pressure stabilizes.
Gradually decrease (or increase) the pressure point by point until it reaches the lower limit (or zero point) of the measurement, and record the reverse stroke output values of each checkpoint in reverse order.
A round trip between the forward and reverse travel verification constitutes one cycle. Pressure sensors with an accuracy level below 0.1 (including 0.1) should undergo three consecutive cycles; Pressure sensors with an accuracy level higher than 0.05 (including 0.05) should perform at least 4 consecutive cycles.

4、 Calibration result processing
Data calculation: Based on the calibration records, calculate the arithmetic mean of the positive and negative travel calibration readings for each calibration point.
Error calculation: Calculate the repeatability error, return error, and linear error of the pressure sensor to ensure that they do not exceed the absolute value of the allowable basic error.

5、 Calibration certificate and records
Calibration certificate: After calibration is completed, a calibration certificate should be issued, indicating the calibration date, calibration results, calibration personnel, and other information.
Calibration records: During the calibration process, detailed data should be recorded, including the selection of calibration points, calibration results, error calculations, etc., for subsequent analysis and reference.

In summary, the JJG 860 calibration method needs to be strictly carried out in accordance with the regulations to ensure the accuracy and reliability of the pressure sensor.

Company Background Introduction：

Ze Heng The advantage of Huapu in metrology calibration, verification, and confirmation is that it focuses on providing quality control services for biopharmaceuticals. It is very familiar with some special instruments, and its main team comes from pharmaceutical companies and instrument manufacturers, who are familiar with instrument and GMP regulations. For example, our team has specially developed a fluorescence quantitative PCR instrument calibration device to replace imports, which greatly reduces the cost of fluorescence quantitative/qualitative PCR instrument calibration (far lower than other peers); We have developed an internal calibration protocol for the cell counter; Developed internal calibration procedures for cell recovery instruments; The calibration procedure of gel electrophoresis scanner was developed; We have developed integrated wireless probes for lower and higher temperatures required for temperature verification, reducing the cost of users using probes extensively and replacing imports; There are many more examples, as we all come from a biological background, we pay attention to the process requirements of every biological user, focus on biopharmaceutical instruments and equipment, and strive to "go with quality and do instrument and equipment quality control" in order to make biopharmaceuticals safer.

We work closely with other units in terms of services, including mandatory inspections, special inspections, or services that cannot be done, to help customers send and collect items on their behalf, saving time, effort, and convenience.

Ze Heng Huapu is a professional service provider dedicated to providing laboratory instrument calibration, instrument and equipment validation, and factory validation for the biopharmaceutical industry. We provide pharmaceutical clients with one-stop quality control outsourcing services for QC/QA/engineering/validation/production departments.