Pressure sensor selection and installation common problems - Database & Sql Blog Articles

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The selection and installation of pressure sensors is directly related to the accuracy of pressure measurement, so we must pay great attention. The following summarizes some common problems and installation precautions for pressure sensor selection, and lays the foundation for proper use of pressure sensors.

Pressure sensor selection frequently asked questions

The pressure sensor needs to maintain stability after working overtime.

Most pressure sensors produce "drift" after over-exhaustion, so it's important to understand the stability of the sensor before purchasing. This pre-work can reduce the hassle of future use.

Pressure sensor package

The packaging of the pressure sensor is often easy to ignore as its frame, but this will gradually reveal its shortcomings in later use. When purchasing a pressure sensor, you must consider the working environment of the sensor in the future, how to humidity, how to install the sensor, whether there will be strong impact or vibration.

What kind of pressure does the pressure sensor need to measure?

First determine the maximum value of the measured pressure in the system. Generally, you need to select a sensor with a pressure range that is about 1.5 times larger than the maximum value. This is mainly due to the fact that in many systems, especially water pressure measurement and processing, there are peaks and constant irregular up and down fluctuations, which can damage the pressure sensor. A sustained high pressure value or slightly exceeding the sensor's nominal maximum value will shorten the life of the sensor, which will also reduce accuracy. A buffer can then be used to reduce the pressure glitch, but this will reduce the sensor's response speed. Therefore, the pressure range, accuracy and stability should be fully considered when selecting a pressure sensor.

What kind of excitation voltage is selected

The type of output signal determines how the excitation voltage is selected. Many transmitters have built-in voltage regulation, so their supply voltage range is large. Some pressure sensors are quantitatively configured and require a stable operating voltage. Therefore, the operating voltage determines whether a sensor with a regulator is used. When selecting a transmitter, the operating voltage and system cost must be considered.

Do you need interchangeable pressure sensors?

Determine if the required pressure sensor can accommodate multiple use systems. This is generally important, especially for OEM products. Once the product is delivered to the customer, the cost of the customer's calibration is considerable. If the product is interchangeable, even changing the transmitter used will not affect the overall system.

What kind of pressure medium

Viscous liquids and mud can block the pressure interface, and solvents or corrosive substances will not damage the materials in the pressure sensor that are in direct contact with these media. These factors will determine whether to choose a direct barrier and a material that is in direct contact with the media.

Pressure sensor temperature range

Usually a pressure sensor will calibrate two temperature segments, one of which is the normal operating temperature and the other is the temperature compensation range. The normal operating temperature range is the temperature range when the sensor is not damaged during operation. The temperature compensation range may not reach the performance specifications of its application.

The temperature compensation range is a typical range that is smaller than the operating temperature range. In this range, the working sensor will definitely reach its performance index. Temperature changes affect its output in two ways, one is zero drift, and the other is the full-scale output.

Pressure sensor output signal

mV, V, mA and frequency output digital output, the choice of output depends on a variety of factors, including the distance between the sensor and the system controller or display, whether there is "noise" or other electronic interference signals, whether an amplifier, amplifier Location and so on. For many OEM devices with short distances between sensors and controllers, the most economical and effective solution is to use a mA output pressure sensor.

Pressure sensor installation precautions

The correct installation position of the pressure sensor on the process pipe is related to the measured medium. In order to obtain the best measurement results, the following should be considered:

1. Prevent the pressure sensor from coming into contact with corrosive or overheated media;

2. Prevent dross from depositing in the conduit;

3. When measuring the liquid pressure, the pressure tap should be opened on the side of the process pipe to avoid sedimentation.

4. When measuring the gas pressure, the pressure tap should be opened at the top of the process pipe, and the sensor should also be installed in the upper part of the process pipe so that the accumulated liquid can be easily injected into the process pipe.

5. The pressure guiding tube should be installed in a place with small temperature fluctuations;

6. When measuring steam or other high temperature medium, it is necessary to add a condenser such as a buffer tube, and the operating temperature of the pressure sensor should not exceed the limit.

7. When freezing occurs in winter, the pressure sensor installed outside should take anti-freezing measures to prevent the liquid in the pressure inlet from expanding due to the volume of ice, leading to damage to the sensor.

8. When measuring the pressure of the liquid, the pressure sensor should be installed in a position to avoid the impact of the liquid to prevent the sensor from being damaged by overpressure.

9. When wiring, pass the cable through the waterproof joint or the coil and tighten the seal nut to prevent rainwater and the like from leaking into the pressure sensor housing through the cable.