Expert’s answer: Level calculation for pressure transmitter with capillary

So, you need to learn how to do level calculation for pressure transmitter with capillary? Okay, here’s what you need to know:

Level calculation never changes on a differential pressure transmitter; once you understand the equation, you can do any other range calculation. Now, there are several types of DP pressure installations to level measurement; I’ll give you a step by step based on your problem.

Level calculation for pressure transmitter with capillary
Example sent by the customer

Level at 0%

  • HP – LP
  • (Height H side x Capillary density) – (Height L side x Capillary)
  • (1000 x 1.02) – (6000 x 1.02)
  • 1020 – 6120
  • DP0% = – 5100 mmWC

Level at 100%

  • HP – LP
  • (Height H process side x Process density) + (Height H side x Capillary density) – (Height L side x Capillary)
  • [(5000 x 0.89) + (1000 x 1.02)] – (6000 x 1.02)
  • [4450 + 1020] – 6120
  • 5470 – 6120
  • DP100% = -650 mmWC

Instrumentation training courses:

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