OMGEMN1.41
GEM2000 Range Gas Analysers
Page 34
Copyright 2009 Geotechnical Instruments (UK) Limited
Note:
When the anemometer is not in use the conical fitting should be placed over
the probe to protect it.
The anemometer must fit centrally (the conical fitting must be set on the probe to half the
pipe ID before insertion). The arrow on the tip of the probe must point in the direction of
the flow.
Note:
Use the thumb screw to align the direction of the probe.
Flow readings are most accurate when there is laminar flow (not turbulent). Turbulence
can be caused by a change in pipe direction or restriction. Ideally, upstream you want at
least 20 times the pipe ID along the length of the pipe without restriction or bend.
Downstream, you want at least five times the pipe ID along the length of the pipe i.e. for a
100mm ID you need 2000mm of clear pipe upstream, 500mm downstream.
Example to Show Anemometer Fitting into the Sample Point:
Instructions for Use:
1)
Attach the anemometer to ‘Connector E’.
2)
Place the anemometer into the borehole ready to take the reading.
3)
For further detail please refer to the process diagrams for ‘Taking Gas and Flow
Measurements’. Go to the ‘Flow Measurement’ screen and the ‘Read Anemometer’
screen is displayed.
4)
When the reading has stabilised press the ‘Enter’ key to store the reading.
Conical Fitting
Pipe Centre Line
Pipe
Head
Flow Direction
Thumb Screw
Anemometer
Conical Fitting
Pipe Centre Line
Pipe
Head
Direction of the arrow must be in the same direction as the flow
Flow Direction
Thumb Screw
Anemometer
Conical Fitting
Pipe Centre Line
Pipe
Head
Flow Direction
Thumb Screw
Anemometer
Conical Fitting
Pipe Centre Line
Pipe
Head
Direction of the arrow must be in the same direction as the flow
Flow Direction
Thumb Screw
Anemometer
