Pressure sensors are a commonly used type of sensor, widely used in various industrial automation environments, including petrochemicals, oil wells, power, shipbuilding, machine tools, pipelines, water conservancy and hydropower, production automation, railway transportation, intelligent buildings, aerospace and many other industries. There are many types of pressure sensors, which leads to different applicable environments. Let's take a brief look at some common pressure sensors.
Ceramic pressure sensor
Ceramic pressure sensors are based on the piezoresistive effect. Pressure acts directly on the front surface of a ceramic diaphragm, causing a slight deformation. A thick-film resistor is printed on the back of the ceramic diaphragm, forming a Wheatstone bridge. Due to the piezoresistive effect of the piezoresistive resistor, the bridge generates a highly linear voltage signal that is proportional to the pressure and also proportional to the excitation voltage. Standard signals are calibrated to 2.0/3.0/3.3 mV/V, etc., depending on the pressure range, and are compatible with strain gauge sensors.
Sapphire pressure sensor
Sapphire pressure sensors utilize the strain gauge principle and employ silicon-sapphire as the semiconductor sensing element, exhibiting outstanding metrological characteristics. The silicon-sapphire semiconductor sensing element is insensitive to temperature changes and maintains excellent operating characteristics even at high temperatures; sapphire has extremely strong radiation resistance; furthermore, silicon-sapphire semiconductor sensing elements exhibit no pn drift.
Intake pressure sensor
The intake manifold pressure sensor detects the absolute pressure in the intake manifold behind the throttle valve. It detects changes in absolute pressure within the manifold based on engine speed and load, then converts this into a signal voltage and sends it to the engine control unit (ECU). The ECU uses this signal voltage to control the basic fuel injection quantity. There are various types of intake manifold pressure sensors, including capacitive and piezoresistive types. Due to their advantages such as small size, flexible installation, fast response time, and high detection accuracy, piezoresistive sensors are widely used in D-type injection systems.
Explosion-proof pressure sensor
The pressure transmitter uses a high-performance pressure-sensing chip, combined with advanced circuit processing and temperature compensation technology, to convert pressure changes into linear current or voltage signals. The product is compact and easy to install, and features a stainless steel housing for corrosion protection. It is suitable for measuring gases, liquids, and other media whose materials are compatible with those of the contact parts. It can be used to measure negative pressure, gauge pressure, and absolute pressure.
Manifold Absolute Pressure (MAP) Sensor
The MAP sensor, located near or inside the vehicle's intake manifold, measures the power load applied to the engine at any given time. The sensor compares these measurements to a vacuum level to ensure consistency. The MAP sensor is important in applications because external factors reported by it can lead to higher engine loads and greater demand on fuel throughput. For example, if the vehicle begins climbing a hill, the MAP sensor should show low vacuum and high engine load.
