Talking about the comparison of various sensors
at present, there are several main piezoresistive sensors on the market: Ceramic piezoresistive, diffused silicon piezoresistive, strain gauge piezoresistive, micro melting piezoresistive. Due to its large volume, capacitive type is generally used to assemble 3051 type pressure transformer, and some small pressure transmitters with small range are also made with capacitance
the author believes that at present, the accuracy of 0.25% in most industrial sites has basically met the requirements. I mean the total error. I think it is generally around 0.5% in China now, of course, there are good and bad. According to the packaging methods of these sensors, the price, sealing, overload, stability, accuracy and measurement range are compared
ceramic piezoresistive type:
low price, relatively simple process
poor sealing, strict mechanical size requirements for the installation of ceramic sensors, sensors can only be sealed in the form of O-rings at the bottom, and are easy to be affected by installation stress
the overload performance is poor. Because the ceramic sensor has less than twice the overload capacity and the demand is increasing, its sensor output is small, so it cannot use a large range to modulate a small range transmitter
the safe overload range is not more than 1.5 times, and three to four times the diaphragm will burst
the stability is general: This is multifaceted, but the protection can save a lot of money
the accuracy is general: the same as above
range: small range can't be done, large range dare not use
diffused silicon piezoresistive type:
the price is expensive, the production process is complex
the sealing property is good: diffused silicon uses O-ring seal, The O-ring has been fixed on the cylindrical base of the sensor, and the requirements for installation size are general
the overload in 2010 is general: the sensor signal is large, and a large range sensor can be used to gradually form a cooperative dependent community of interests to modulate a small range transmitter, but the pressure is transmitted to the sensitive element through silicone oil, and the liquid is easy to produce secondary hydraulic impact
high stability: because the pressure is transmitted through the oil, the sensor has the best stability
high accuracy: ditto
good range: it is also the best of these sensors, but it is not suitable for measuring mbar pressure. This point refers to the diffusion silicon elder Keller
glass micro melting:
general price
high sealing: there is no possibility of leakage, several are the best
high overload: several are the best. The signal of the sensor itself is large, which is suitable for small range
good stability: it is done by large manufacturers, and the process is guaranteed.
good accuracy: the same as above.
range: it can't be done in a small range, and it should not be said that it should be chips below 2bar. Not used. The performance of the above parameters is determined by the inherent packaging form of the sensor, and the specific performance depends on the process of the sensor manufacturer
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