As early as 1930, the first pressure sensor appeared. Until now, sensor technology has continued to develop. Newly developed or produced pressure sensors must be fully tested for their technical performance to ensure the accuracy of their measured values.
At present, the basic calibration method is to use a pressure controller, which provides a stable known pressure input to the pressure sensor to be calibrated. After obtaining the output of the pressure sensor, the pressure sensor input and output are processed and compared to obtain a series of curves that characterize the corresponding relationship between the two, thereby obtaining the actual measured results of the performance indicators of the pressure sensor.
The pressure sensor is calibrated during the production process. Its essence is to use the high-precision pressure sensor in the pressure controller or calibrator to compare and set the low-precision pressure sensor.
1.Development of Pressure Sensors
Automation of pressure sensor production began in the late 1960s with the development of the Texas Instruments Model 156 Gram-and-Meter Tester.
In the early to mid-1970s, new and improved features emerged, including computer interfaces that allowed for full automation, and forced balancing that virtually eliminated the hysteresis and nonlinearity of quartz Bourdon tube pressure sensors.
Other pressure measurement technologies, such as strain gauges, reduced costs and enabled faster pressure control. However, the overall performance of these sensors was far inferior to that of quartz sensors. As the performance of low-cost sensors improved, these technologies became increasingly popular with pressure controller manufacturers.
In the 1980s, the miniaturization of computers led to significant improvements in pressure sensor performance. This enabled pressure controller manufacturing companies to use new, higher performance, lower cost pressure sensors in their products, and as microcomputers, along with improved materials and experience, many different pressure control methods were developed, such as leak control, positive pressure, and pulse width modulation. Each of these control methods provided users with more options, resulting in lower costs and increased speed, and higher levels of measurement accuracy.
In the 1990s, multi-channel pressure controllers were introduced, allowing 2 or more independently controlled pressures to be achieved with a single pressure controller. This led to further modularity, where users could replace the internal pressure sensor to achieve a wider range of pressure control and measurement.
2. Pressure control stability
This has shifted the focus from the previous single measurement performance to the simultaneous consideration of pressure control capabilities.
It is recognized that better pressure control, especially at low pressures, is as important as the measurement accuracy provided by the reference pressure sensor.
Pressure controllers now offer many software-based functions, faster and more computer interfaces, different pressure accuracy and sensor modules.
There are also various pressure control types available, some offering high speed and lower control accuracy, and some offering higher control accuracy but longer time to achieve the set point.
This means that for sensor manufacturers (who make a variety of pressure sensors, from low pressure to high pressure and from low accuracy to high accuracy), they must invest in many different pressure control standards.
The pressure controller model used in the manufacturing of a low pressure sensor may be different from the pressure controller model used in the manufacturing of a high pressure sensor; the pressure controller model used in the manufacturing of a low accuracy sensor may be different from the pressure controller model used in the manufacturing of a high accuracy sensor.
What to consider when choosing a suitable controller
Even though automatic pressure controllers have evolved to meet more needs of sensor production managers, they have not yet met their greatest need for a single pressure controller to meet all current and future needs of sensor manufacturers.
3. New pressure sensor
Modular gas pressure controller calibration
— 6270A / 8270A / 8370A
Multiple workloads - fast, accurate and reliable
Ideal for pressure sensor manufacturers, modular design makes it very easy to maintain, high-speed control within a wide range and high accuracy make it able to meet various production capacity needs.
● Maintenance and repair without stopping production:
Fully modular design, fast replacement maintenance and repair
● Lower entry cost:
100:1 control adjustable ratio, one controller is equivalent to multiple controllers
● One controller meets all needs:
PM200/PM500/PM600 three specifications, flexible configuration of multiple ranges
● Pollution-free production:
100MPa full range coverage of gas pressure, providing the easiest to use gas high pressure standard
