Differential pressure measurements are used in many branches of industry for various measuring tasks. Besides mechanical measurements via active pressure lines or chemical seals, electronic differential pressure measurements are now also available. But what is the optimum solution for the user? This article explains the operating mode as well as the differences between the systems. It focuses particularly on the measuring accuracy, delivers decision-making support and gives practical examples.
An innovative software and hardware concept makes it possible to combine any two pressure transmitters of the VEGABAR 80 series into an electronic differential pressure system. Electronic differential pressure measurement is often used for filters, pumps and pipelines.
The advantages
- Simple installation
- Multi-variable sensor: Differential pressure, static pressure and temperature
- Not affected by ambient conditions
The mechanical differential pressure measurement always operates according to the same principle independently of its manufacturer: Two pressure values are applied to a differential pressure transmitter. Active pressure pipes or capillaries bring the process so to speak from the measuring point to the field instrument. The measuring cell calculates the difference mechanically which, after transformation, is emitted in an electrical signal and output as a measured value.
The electronic differential pressure measurement differs: There, the pressure values are measured individually at the measuring points by a primary/secondary sensor pair. The two instruments are electrically connected; the pressure difference is electronically emitted in the primary sensor. The following figure shows the differences by giving an example of a level measurement in a pressurised vessel.