Selection rules for pressure transmitters
From: Issued date 2021.03.25 Back
Pressure transmitter is the most commonly used sensor in industrial practice. It is widely used in various industrial automatic control environments, including water conservancy and hydropower, railway transportation, intelligent buildings, production automatic control, aerospace, military, petrochemical, oil wells, power, ships, machine tools, pipelines and many other industries. With the wide application fields, the types of pressure transmitters are also increasing, so how to choose the correct pressure transmitter?
1. Depending on the type of pressure to be measured
2. Pressure types are mainly gauge pressure, absolute pressure, and differential pressure. Gauge pressure refers to the pressure less than or greater than atmospheric pressure based on the atmosphere; absolute pressure refers to the absolute zero pressure as the reference, which is higher than the absolute pressure; differential pressure refers to the difference between two pressures.
2. According to the measured pressure range
In general, the actual measurement pressure is selected as 80% of the measurement range.
3. According to the tested medium
According to the different measurement media, it can be divided into dry gas, gas liquid, highly corrosive liquid, viscous liquid, high temperature gas liquid, etc. Correct selection according to different media will help extend the life of the transmitter.
4. According to the maximum overload of the system
The maximum overload of the system should be less than the overload protection limit of the transmitter, otherwise it will affect the life of the transmitter and even damage the transmitter. Generally, the safe overload pressure of a pressure transmitter is twice the full scale.
5. Accuracy level as needed
The measurement error of the transmitter is divided according to the accuracy level. Different accuracy corresponds to different basic error limits (expressed as a percentage of full-scale output). In practical applications, the selection is based on the control requirements of measurement error and in accordance with the principle of economic use.
6. According to system operating temperature range
The temperature of the measuring medium should be within the operating temperature range of the transmitter. If it is used at an excessive temperature, it will cause a large measurement error and affect the life of the transmitter. During the production process of the pressure transmitter, the temperature will be measured and compensated to ensure that the measurement error caused by temperature is within the range required by the accuracy level. In the case of high temperature, you can consider choosing a high-temperature pressure transmitter or taking auxiliary cooling measures such as installing condensing pipes and radiators.
7. According to the compatibility of the measuring medium and the contact material
In some measurement occasions, the measurement medium is corrosive. At this time, materials compatible with the measurement medium or special processing needs to be selected to ensure that the transmitter is not damaged.
8. According to power supply and output signal
The pressure transmitter is usually powered by a DC power supply and provides a variety of output signal options, including 4-20mA.DC; 0-5V.DC; 1-5V.DC; 0-10mA. DC, etc., can have 232 or 485 digital output.
9. According to on-site working environment and other situation
Whether there is vibration and electromagnetic interference, etc., the relevant information should be provided when selecting, so as to take corresponding treatment. In the selection, other methods such as electrical connection can also be considered according to the specific situation.
Nanjing Wotian is a manufacturer specialized in producing pressure sensors, pressure transmitters, level transmitters, etc. for 15 years. Its excellent quality, wide range, complete range and short delivery time have been well received by domestic and foreign customers . If you have any needs, you can contact hotline 400-8508-330 at any time, We are waiting for your call here.