Instruction Manual

Device type
The type of connected Data Logger is indicated under Device type:
- sealed gauge, air pressure compensated in each case (DCX-22 VG and DCX-22 AA)
- absolute (DCX-22 SG), air pressure must be compensated separately (see Airpressure-
Compensation-module)
Conversion to
Recorded hydrostatic pressures can be converted into length values as per the water level
configuration settings. This conversion is carried out by means of the module Waterlevel-Converter.
Height of water above water level sensor (e):
- Linear measure (e) from the water level sensor to the
water surface. The height (e) is directly determined
from the hydrostatic pressure, the density of the
medium and acceleration due to gravity.
Depth to water (f):
- f = B - e = C + D -e
Height of water above sea level (g):
- g = A - f = A - (B - e) = A - (C + D - e)
Starting conditions at installation
Height of wellhead above sea level (A):
- During conversion to "Height of water above Sea
Level (g)", the height of the wellhead above sea level
must also be specified. Any other desired reference
point may also be used.
If the sea level, or the reference point selected
instead, is located above the well head, the value
must be entered with a negative sign.
Installation Depth (B):
- This value must be determined at sensor installation. It should correspond to the length from
the upper edge of the wellhead to the sensor-membrane. The membrane is identified by a
mark on the sensor.
Depth to water. (C):
- If this start condition is selected, the sensor measures the water height above the sensor (D)
at the start of the recording Write Configuration and uses the value entered here to
determine the installation depth of the water level sensor. (B).
Offset:
- Offset is a freely selectable value (positive or negative) which is added to the length
calculated. The default value is 0. For example, by giving a value for Offset, the distance
between the upper edge of the wellhead and the earth’s surface can be specified and
therefore taken into consideration during the calculation.
Operating Manual for Logger DCX 4.0 KELLER AG Page 15