What is a Pressure Sensor?
Pressure sensors control and monitor thousands of everyday applications. They can also indirectly measure other variables such as fluid/gas flow, speed, water levels and altitude.
Pressure Sensors do this by measuring the force required to stop a fluid or gas from expanding per unit area. They also measure fluid or gas flow speed and also act as transducers. They convert the input (mechanical pressure) into an electrical output signal. These sensors often use piezoresistive technology. This is because the piezoresistive element changes the electrical resistance proportional to the pressure experienced. Thus making it easy to measure the pressure applied.
There are a variety of sensors. The type of sensor you use depends on size, capacity, measurement method, sensing technology and output requirements. They can also go by different names. These include: pressure transducers, pressure transmitters, pressure senders, pressure indicators, piezometers and manometers.
How Does it work?
At Metromatics, we supply a range of FUTEK pressure sensors. These sensors work by using the piezoresistive effect. This means a metal foil strain gauge converts applied force, pressure, tension, compression, torque and weight into a change in electrical resistance. This resistance provides a pressure measurement.
Strain gauges work because they are electrical conductors. They tightly attached to a film in a zigzag shape. When pulled, the film stretches and elongates. Alternatively, when pushed, it contracts and gets shorter. The elongation or contraction then creates an electrical output signal with a pressure measurement.
Types of Pressure Sensors
Pressure sensors vary in the types of measurements they provide. Their pressure sensing technology and transducer types can also vary. For the purpose of this article here are 4 different types of pressure sensors.
Differential Pressure Sensor
This sensor measures the difference between two pressure values or points within a system. It also has two ports that measure and calculate differential pressure.
Absolute or Vacuum Pressure Sensor
This sensor measures absolute pressure. Absolute pressure is a pressure measurement relative to a perfectly sealed vacuum. These sensors are perfect for situations that require a constant reference. Example of this include vacuum pumps, liquid pressure measurements, industrial packaging, industrial process control, aerospace and aviation inspections. Finally, this type of sensor is especially perfect for barometric measurements or altimeters.
Gauge or Relative Pressure Sensor
Gauge pressure is differential pressure measured differently but always relative to the local ambient pressure. Absolute pressure can also be considered differential pressure if the measured pressures is compared to a perfect vacuum. Furthermore, changes in atmospheric pressure due to weather or altitude directly influence the output of a gage pressure sensor. Therefore resulting in positive pressure (when gauge pressure is higher than ambient pressure) or negative pressure (measured pressure below atmospheric pressure).
What is a Pressure Switch?
A pressure switch turns on at a set point and off at a cut out point. For example, a water pump with a pressure switch will only start after the switch releases a certain amount of water from its reservoir. As a result ensuring the safety of the machine and its operators.
Pressure Sensors by FUTEK
Pressure sensors can vary drastically in technology, design, performance, application suitability and cost.
The FUTEK PFP350 is a general sensor with plug and cable. It is made from 17-4 stainless steel and weighs only 155 grams. It also has mV/V standard output range and amplified VDC or 4-20mA as per request. Secondly, like the majority of FUTEK sensors it uses metal foil strain gauge technology.
The FUTEK PMP450 is an Industrial Pressure Sensor. It has a wide range of electrical connection and process connection options. This sensor also has a welded stainless steel measuring cell for improved media compatibility. Finally it has no internal soft sealing materials. As a result it won’t react with the media or deteriorate over time.
The FUTEK PFT510 is a miniature pressure sensor. It is made from 17-4 Stainless Steel and weighs only 25 grams. It also has has mV/V standard output range and like the majority of FUTEK sensors it uses metal foil strain gauge technology.
The FUTEK PMP300 is Pressure Sensor for OEM applications. It has a rugged design and is resistant to vibration, shock, wide temperature variations, RFI and other extreme environmental conditions. This unit is usually found in industrial and OEM pressure transducer applications.
Furthermore, this sensor also has no internal soft sealing materials. As a result, it shouldn’t react with the media or deteriorate over time. Finally, it’s also enhanced by the stainless steel welded measuring cell that protects it.
The FUTEK PMP410 is a Stainless Steel Pressure Sensor for rugged OEM applications. It has a rugged design and is resistant to vibration, shock, electro magnetic interference and other extreme environmental conditions. It also contains a standard 4-20mA signal output. Furthermore, other outputs, process connections and electrical connections are also available and individually temperature compensated.
This sensor also has no internal soft sealing materials. As a result, it shouldn’t react with the media or deteriorate over time. It is also enhanced by the stainless steel welded measuring cell that protects it.
For more information about the FUTEK pressure sensors we carry please click here.