How to measure level by bubbler method?

Field Instrumentation
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Level measurement using bubbler method

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in sump,

1: mark 0 % and 100 %

2: measure distance between 0 and 100%

3: put the range in tx.

4: set air flow regulator and rotameter.

5: check the calibration

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The correct method of level measurement includes Specific Gravity (S.G) compensation. The method above is valid only for hydrostatic level measurement of water, which has a S.G. of 1.00.

  • Determine the maximum physical level to be measured in units of water column: mmH2O or mH2O, which is the vertical distance or elevation above the bottom of the dip tube. If the physical level is some oddball value like 11.23m, the number can be rounded up to an even number like 12.00m which is easy-to-understand when scaled for an HMI display.

  • Multiply the maximum physical level value by the liquid’s S.G. example: 12.00m * 1.22 = 14.64mH2O = 20.00mA

  • the product value, 14.64mH2O is the URL value for the hydrostatic pressure transmitter

  • the receiver device (indicator. HMI, DCS, controller, PLC AI) interprets the 14.64mH2O @ 20.00mA as 12.00 physical meters of level.