Xylem Expert 800-900 - Manual (Page 5)

Manual
GB Manual Expert Log 800-900.doc
5
Absolute measurement (Expert 800)
The Expert 800 instruments utilize an absolute pressure sensor. A second
Expert 800 is positioned on the surface as a barometer where low water depths
are involved (as the influence of air pressure fluctuations must also be taken into
consideration), and the air pressure characteristic is recorded. The water level
is then calculated in the PC program (MJK Log Link) as the difference between
the two measured values.
The Expert 800 should be pulled out of the measuring position to read out the
data. The interface connector is located in the instrument itself. The Expert 800
can be utilized with extreme flexibility, due to the fact that it has no cable.
In contrast to the Expert 800, the Expert 900 is fitted with a cable with a read-out connector on its end.
It is therefore possible to read out the Expert 900 without removing it from the measuring position.
The Expert 900 utilizes a reference tube for air pressure compensation (which acts as a barometer)
and automatically calculates the difference between the two measuring values. This enables a direct
read-out of the water level.
Expert 900 Expert 800
Installation
Read-out units
Rope
Water
surface
Reference- line of sensor