Several regulations for selecting pressure point of pressure transmitter

Selecting pressure points for pressure transmitters shall meet the following requirements:

1. When measuring gas pressure, the pressure point should be in the upper part of the process pipeline.

2. When measuring the liquid pressure, the pressure point should be within the range of 0ο~45ο included angle between the lower half of the process pipeline and the horizontal center line of the process pipeline.

3. When measuring steam pressure, take pressure points within the range of 0 ~45 degrees between the upper half and the lower half of the process pipeline and the horizontal center line of the process pipeline.

4. The installation position of pressure source components should be in the pipe section with stable process medium flow.

5. When the pressure source component and the temperature source component are on the same pipeline, the pressure source component should be installed on the upstream side of the temperature source component.

6, the end of the pressure source parts should not exceed the inner wall of the process equipment and process pipeline.

7. When measuring the pressure of turbid media such as dust, solid particles or sediment on the vertical process pipeline, the source parts should be installed obliquely upwards, and the included angle with the horizontal line should be greater than 30 degrees, and the downstream beam should be installed at an acute angle on the horizontal process pipeline.

8. The installation position of pressure transmitter should be well lit, easy to operate and maintain, and should not be installed in places with vibration, humidity, high temperature, corrosiveness and strong magnetic field interference.

9. The installation position of the pressure transmitter should be as close as possible to the source taking part. The installation height of the transmitter for measuring low pressure should be consistent with the height of the pressure point, especially for measuring liquid medium and condensable gas medium.

10. When measuring the pressure of gas medium, the installation position of the transmitter should be higher than the pressure point, and when measuring the pressure of liquid or steam, the installation position of the transmitter should be lower than the pressure point, in order to reduce the additional facilities for exhaust and drainage.

Positive and negative migration of pressure transmitter

Transmitter migration means that the measuring point of the transmitter is artificially moved from zero to a fixed value, and the initial measurement value is greater than zero, which is called transmitter positive migration; The initial value is less than zero, which is called transmitter negative migration.

Purpose of transmitter migration:

1. Through the positive migration of the transmitter, the measurement accuracy and sensitivity are improved and the quality of the regulating system is improved.

2. Through the negative migration of the transmitter, the working range enters the negative pressure area and the functions of the transmitter are expanded.

3. Transmitter migration can balance the absolute value of the lower measurement limit of static pressure transmitter after migration brought by different installation heights, which should not be greater than the upper measurement limit of range code (for example, range code 4 should not be less than -37.4kPa).

At atmospheric pressure, it shall not exceed one engineering atmospheric pressure.

Give an example to illustrate the positive migration of the transmitter:

If the measuring range of the transmitter is 0-25kPa and the transmitter is moving to 5-30kPa, the starting and adjusting steps are as follows:

1. Adjust the transmitter within the range of 0-25kPa.

2. Add a pressure of 5kPa to the high-voltage side of the transmitter, and then adjust the zero position of the transmitter until the output is 4mA. Note: The transmitter range cannot be adjusted.

Give an example to illustrate the negative migration of the transmitter:

If the measuring range of the transmitter is 0-25kPa and the transmitter moves negatively to-30 kPa ~-5 kPa, the starting and adjusting steps are as follows:

1. Adjust the transmitter within the range of 0-25kPa.

2. Add a pressure of 30kPa to the low-voltage side of the transmitter (the output is adjusted to 4mA, which is the zero point of 30kpa; when the pressure disappears, it becomes -30kPa), and then adjust the zero point of the transmitter until the output is 4mA. Note: The transmitter range cannot be adjusted.

Link-B2B is a professional supplier listing service platform which will provide high quality and trustworthy supplier list to international buyers. If you are looking for pressure transmitters suppliers, feel free to visit Link-B2B.com and send a request.