How can you use a differential pressure measurement device to measure a negative pressure if it has been factory configured to measure a positive pressure range without making any adjustments to the electronics or the signal output?
Finding a pressure sensor to read negative pressure can be difficult since the vast majority of pressure measurement devices are only available with positive ranges as standard, since most applications require a positive pressure range, and therefore manufacturers understandably focus on the most popular pressure ranges for their product range.
Although manufacturers will often consider a custom configuration for measuring negative pressure, this could cause a delay to delivery and an extra cost compared to the standard pressure range configuration.
Featured differential pressure measurement products
Wet / Wet Differential Pressure Sensors - Wet/Wet differential pressure transducers and transmitters which are compatible with liquids on both positive and negative side process connections.
Clean room monitoring system to measure pressure, humidity & temperature in 4 individual rooms - A complete clean room measurement system for 4 separate rooms, each with its own room pressure, humidity and air temperature indicator, and a central monitoring unit for clean room corridor or control room.
There is a much simpler and convenient solution to measuring negative pressures. A differential pressure measurement device has two separate pressure connections so that the difference in pressure between the two connections can be measured. One connection will be marked as High (Hi) or Positive (+), and the other as Low (Lo) or Negative (-).
Typically when measuring positive pressures, the Low side connection would be open to ambient air pressure, and the High side connection would be connected to the positive pressure to be measured.
If you want to measure negative or suction pressure instead, you can reverse the connection, so that the High side connection is open to ambient air pressure, and the Low side connection is connected to the vacuum pressure. As the vacuum increases, the greater will be the difference in pressure between the Low and High side.
As an example, a 0 to +100 mbar differential pressure range will become a 0 to -100 mbar differential pressure range simply by reversing the connections.
Featured differential pressure measurement products
ADT681 Digital Pressure Gauge - The ADT681 digital pressure gauge family covers a wide range of pressures from as low as 1 inH20 differential to as high as 36,000 psi gauge.
DPS300 User Switchable Pressure Range, Volts or Current Output Low DP Sensor - The DPS 300 is a low range HVAC differential pressure sensor. The lowest possible pressure range is 0...100 pascals. 2 or 3 switchable pressure ranges, plus volts or current output are included with most standard configurations.
Featured differential pressure measurement products
1 hPa Positive Room Pressure Sensor, Switch & Display - A 100 Pascal range positive room pressure sensor with a 0-10 volt analogue output signal relating to the inside/outside room pressure difference.- 10Pa diff range 0-20mA output air pressure sensor for automotive component testing - A very low range pressure sensor for automotive component testing use to measure pressure of air over a range of 0 to 10 Pa diff from two barbed tube hose connections, and sending the corresponding 0-20mA signal through the DIN plug electrical connection.
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