Precautions when using thermal gas mass flow meter

sales01@cxflowmeter.com


Thermal mass flow meter is a special instrument for gas measurement. Different from other gas flow meters, it does not need pressure and temperature correction,
and directly measures the mass flow of gas. A single sensor can do the range from very low to high range. The underlying principle is that the rate at which a
fluid absorbs heat is directly related to the mass flow rate. When the moving gas molecules hit the thermal resistance, it absorbs and takes away heat.
The greater the flow rate, the more molecules contact the thermal resistance, and the more heat is absorbed. The heat absorption is related to the number of molecules, thermal characteristics and flow characteristics of a certain gas.


 
Matters needing attention during installation and commissioning of thermal gas mass flowmeter:
1. Requirements for straight pipe sections
When installing, the upstream straight pipe section of the flowmeter is required to be greater than 20D, and the downstream straight pipe section is 10D.
 
2. Confirm the flow direction
There is a small plane at the end of the thermal gas mass flow element near the package. There is an arrow indicating the flow direction of the fluid on this small plane.
When installing, pay attention to the small plane marked with the flow direction arrow and the direction of the flow of the process medium. is the flow arrow pointing in the direction of process medium flow.
 
3. Confirm that the serial numbers of the flow element and the electronic circuit part are consistent
The flow element and the electronic part are matched. If the serial number does not match, the reading will be inaccurate. Special attention should be paid to the initial installation.

4. Avoid installing the sensor on a vibrating pipe.

5. The measurement unit of the output data of the flowmeter and the data displayed by the DCS operation station should be unified, such as SCFM or NCMH, LB/HR or KG/HR.

6. The calibration of the output data of the flowmeter and the calibration of the data received by the DCS control system should be consistent, such as 4~20mA, 0~20mA, 1~5VDC.

7. Electrostatic discharge device (ESD)
The circuit board of this machine is equipped with an electrostatic discharge device when it leaves the factory. It should be paid great attention during installation, and devices
such as megohm resistors with grounding must be used reasonably. Because the flow transmitter contains electrostatic discharge (ESD) sensitive devices, ESD warnings must
be strictly observed when unpacking or handling electronic circuit board assemblies.




If you want to know more detailed parameters and quotations about thermal gas, please contact winny:sales01@cxflowmeter.com