Ray-Level DP Transmitter Level Calculator

Inputs

Mode
0%100%
0%LRV 180.0 mmwc100%URV 630.0 mmwcH1500 mmH2200 mmHPdryLPDP50 %DP 405.0 mmwcSG1 0.90 · dry leg

Results

LRV180.0mmwc
URV630.0mmwc
Range450.0mmwc
Live DP @ 50.0%405.0mmwc
About DP transmitter level measurement

Dry-leg configuration

The LP (low-pressure) leg is open to atmosphere — no liquid fills the reference side. The DP transmitter measures the hydrostatic head of the process fluid on the HP side minus the negligible gas pressure on the LP side.

LRV = H2 × SG1  |  URV = (H1 + H2) × SG1

Wet-leg configuration

The LP leg is filled with a seal fluid (SG2) to prevent the process fluid from entering the transmitter. Its back-pressure subtracts from the HP reading, often producing a negative LRV.

LRV = H2 × SG1 − Y × SG2  |  Y = H1 + H2

H1SpanDistance from 0% to 100% level (mm)
H2SuppressionDatum offset — distance from the HP tapping to the 0% level (mm)
SG1Process SGSpecific gravity of the process liquid
SG2Seal SGSpecific gravity of the wet-leg seal fluid

Formula reference: instrumentationtools.com — DP Transmitter Dry Leg & Wet Leg Calculations