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.
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Monitoring vacuum depression in food powder drying towers with a low range dp transmitter - DP transmitter for precise vacuum measurement and control for coconut powder drying towers to ensure consistent product quality.
Solvent compatible +/-100mWG dp transmitter with PTFE seals - Differential pressure transmitters to use on Nitrogen and/or air containing low levels of flammable solvents.
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.
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20 Pa DP range 0-10V output air pressure sensor for building management use - A low range 20 Pa range differential pressure sensor, ideal for monitoring filters, ventilation ducts, and HVAC systems in commercial and residential buildings.- Using 25 mbar DP sensor on vacuum below 0.2 bar absolute - I would like to measure a differential pressure of 0 to 25 mbar in a vacuum of < 0.2 bar absolute pressure.
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- Low range ATEX approved 100 Pascal range DP transmitter - The DPT200 is a robust ATEX approved differential pressure transmitter which has a very low range of 100Pa.
Low delta P sensor with 200mmH2O range and response time < 5ms - The DMD331 uses silicon technology which is very small compared to other sensing technologies which would have a more limited response time.
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