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Appendix C: Measuring Elevation or Depth-to-Water
In normal configuration, the PT2X returns a pressure measurement relative to the water
above the sensor. This can be expressed in psi, feet of water, inches of mercury, or a
number of other units - however, it is always relative to the water above the sensor.
Often an engineer will need to know the depth-to-water or the elevation of the water.
Using Aqua4Plus’ field calibration abilities, the PT2X can be configured to display
depth-to-water or elevation.
Measuring Depth-to-Water
Dw = Depth to water (measured with water level indicator)
Ds = Depth of sensor submergence (from Aqua4Plus,
Real Time Monitor)
Off = Dw + Ds = Offset (calculated) to be entered in
Aqua4Plus
m = -1 (Slope, Constant)
Example:
Dw = 47’
Ds = 38’
Off = Dw + Ds = 47’ + 38’ = 85’
D w
Ds
To enter the offset, click on the Config Menu, and then select Field Calibration. (Be sure
the units in Aqua4Plus are the same as the units you used when measuring, above.)
For the ‘m’ value under Pressure, enter -1. This is a constant.
For the ‘b’ value under Pressure, enter the offset calculated above, in this case 85.
Click OK. The PT2X will now display Pressure readings as depth to water.
Figure 9: Entering offset for Depth-to-Water readings
Figure 8: Depth-to-
Water Measurements
