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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Climate room pressure, humidity and temperature control using a integrated environmental monitor - Simplify your climate room or cleanroom control system. By combining a dedicated low-range pressure sensor with a multi-parameter controller, you can measure and control pressure, temp, and RH with one device.
41X High Precision Low Range Pressure Transmitter - High precision pressure transmitter for measuring very low vented gauge reference or differential air pressures. Rangeable 4-20mA or 0-10 volt output.
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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Balancing air pressure in marine engine rooms with a low range dp sensor - Low-range bidirectional differential pressure sensor helps maintain the critical air balance in a sealed vessel engine room, ensuring optimal engine combustion and ventilation performance.
20 pascal differential pressure transducer for clean rooms - Voltage output pressure transducer with 0-20 Pa range for cleanroom applications. Provides reliable pressure monitoring to prevent contamination in critical environments.
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Negative room pressure monitor and logger for multiple zones - Monitoring system to measure negative room pressure inside each of five interior zones to eliminate the spread of dust.
Heating appliance chimney draft and barometric pressure testing using differential and absolute sensors - Very low, bi-directional chimney draft pressure and barometric pressure sensor for testing preformance of wood stoves in a research environment.
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