Selection techniques for high temperature pressure transmitters
The key to the selection of high-temperature pressure transmitter is the temperature, especially the high-temperature type. If the wrong pressure transmitter is not used, the following is a seven-step technique for selecting the high-temperature pressure transmitter.
First, the wetted material.
We should consider the medium measured by the pressure transmitter. The material of the contact medium of the general pressure transmitter is made of 316 stainless steel. If your medium is not corrosive to 316 stainless steel, then basically all the pressure changes. The transmitter is suitable for your measurement of the pressure of the medium. If your medium is corrosive to 316 stainless steel, then we need to use a chemical seal, which not only can measure the pressure of the medium, but also effectively prevent the medium from contacting the wetted part of the pressure transmitter. Protect the pressure transmitter and extend the life of the pressure transmitter.
Second, the high temperature type pressure transmitter accuracy distinction
Each type of electronic measuring instrument will have accuracy error, but the accuracy level of each country is different. For example, the accuracy of national standards such as China and the United States is the best part of the linearity of the sensor, that is, we usually The accuracy of the measurement range is between 10% and 90%; the accuracy of the European standard is the worst part of the linearity, which is what we usually call 0 to 10% and 90% to 100% of the measurement inverse. The accuracy between the two. If the accuracy of the European standard is 1%, the accuracy of the standard in China is 0.5%. The accuracy of the pressure transmitter developed by Beijing Koster Automation Equipment Co., Ltd. is 0.2. Pressure transmitter please choose Aote products.
Third, the range of the range.
The maximum range of sensor measurement is 70% of the sensor's full scale is the best, that is, now we need to measure the pressure of 70bar, we should choose the pressure transmitter range of 100bar. Pressure transmitter please choose Aote products.
Fourth, the output signal.
At present, due to various collection needs, there are many kinds of output signals of pressure transmitters on the market, mainly 4~20mA, 0~20mA, 0~10V, 0~5V, etc., but the more commonly used is 4~20mA and 0~10V two kinds. Among the output signals I mentioned above, only 4~20mA is two-wire system (we say that the output is several lines without grounding or shielding), and the others are three-wire system.
Fifth, the medium temperature.
Since the signal of the high temperature type pressure transmitter is partially converted by the electronic circuit, in general, the high temperature type pressure transmitter measures the medium temperature from -30 to +100 degrees. If the temperature is too high, we generally use The condensation bends to cool the medium, which makes the cost of producing a high-temperature pressure transmitter for you to be much lower.
Sixth, measure the medium.
Generally, we measure the relatively clean fluid. We can use the standard pressure transmitter directly. If the medium you are measuring is crystallized or viscous, we usually use an external diaphragm. Or used in conjunction with a chemical seal, this effectively blocks the media from blocking the pressure measurement orifice.
After determining the above six parameters, you must also confirm the process connection interface of your high temperature pressure transmitter and the supply voltage of the pressure transmitter; if you use it in special work prizes, you should also consider the explosion protection level.