High-temperature pressure sensors are sensors with an operating temperature above 125°C. Depending on the technology and materials used, these sensors can be divided into different grades, including high temperature pressure sensors with temperature resistance of 180°C, 300°C, 450°C and 650°C.
Currently, Kulite Semiconductor Products (USA) represents the highest standard in this field worldwide. Their high-temperature pressure sensors based on piezoresistive technology and SOI substrates can withstand temperatures up to 450°C (with experimental values reaching 538°C). Those using silicon carbide (SiC) substrates can endure up to 650°C.
In this article, using the XTEH-7L-190 (M) model as an example to detail how to select and interpret the key specifications of high-temperature pressure sensors.
Figure 1 shows the exterior of the XTEH-7L-190(M) series high-temperature pressure sensor.
According to the product manual, this sensor operates within a temperature range of -75°F to 750°F. It utilizes a leadless packaging technology and offers a high natural frequency, making it ideal for applications such as engine stall prevention and other high-temperature industrial environments.Table 1 is the parameter table of the sensor, which will be explained in detail below.
The table is divided into four sections: Input, Output, Environmental Parameters, and Physical Parameters.
Input Section:
·Pressure Range: This refers to the maximum input pressure the sensor can measure while maintaining rated accuracy. The XTEH-7L-190(M) covers a range from 25 PSI to 3000 PSI. For example, if your application requires measuring pressures up to 1 MPa, a sensor with a 1.5 MPa range is generally suitable. However, this is not absolute. The overload of the pressure sensor and the requirements for measurement accuracy must also be considered.
·Pressure Type: The sensor supports both absolute pressure and sealed gauge pressure. Absolute pressure means that the reference pressure of the measured pressure is vacuum, while sealed gauge pressure uses standard atmospheric pressure as a reference.
·Overload Pressure: Rated at 2x the range. For instance, if the range you choose is 25PSI, then when the pressure he measures reaches 50PSI without permanent damage, though performance may deviate from specified values. When used within the rated range, accuracy remains within nominal values.
·Burst Pressure: Rated at 3x the range. A 25 PSI sensor can endure up to 75 PSI without structural failure, but performance will be compromised, and damage may be irreversible. Accuracy is not guaranteed even when used within the rated range after such exposure.
·Pressure Medium: The types of media that can be directly measured.
Resolution: Infinitesimal, this depends on the accuracy of the acquisition system;
·Natural Frequency Without Protective Screen (kHz): The lowest resonant frequency of the sensor structure, primarily influenced by its shape and size.
·Acceleration Sensitivity: Measurement error introduced by acceleration, which varies by direction.
·Insulation Resistance: Indicates the insulation quality between the sensor's leads and housing.
Environmental Parameters:
·Operating Temperature Range: The full temperature range the sensor can endure.
·Compensated Temperature Range: The range within which the sensor meets specified accuracy. High-temperature sensors often use resistor network compensation, which typically corrects accuracy at three temperature points. Performance may remain within spec slightly beyond this range, but not across the entire operating range.
·Temperature Zero Drift: Change in output with temperature when no pressure is applied.
·Sensitivity Temperature Drift: Change in sensitivity with temperature.
·Acceleration and Linear Vibration Tolerance: The maximum acceleration and linear vibration the sensor can withstand.
Understanding these parameters is essential for selecting the right high-temperature pressure sensor for your application. If you have further questions or need assistance, feel free to reach out to our technical team: Phone Number: +8618066965135; Email: mihuitec@gmail.com
At Mihui, we don't just sell sensors-we provide solutions. Our application engineers are ready to collaborate with you, analyze your requirements, and recommend the most suitable pressure transmitter to ensure reliability, safety, and value.
