GEM2000 Range Gas Analysers
OMGEMN1.41
Copyright 2009 Geotechnical Instruments (UK) Limited
Page 33
7.4 How to Use an Anemometer (Optional)
The GEM2000 range has the facility to attach an anemometer device enabling the site
engineer to measure the flow of gas within an extraction system. The anemometer can be
set to display two values m/s (meters per second) and m
3
/hr (metres cubed per hour).
It is best practice to take the gas reading first before taking the flow reading with the
anemometer attached.
If using a ‘borehole ID’ the internal pipe diameter can be predetermined in the optional
Gas Analyser Manager (GAM). Once set, the site engineer cannot edit the pipe diameter
setting.
If the site engineer is not using a borehole ID or the pipe diameter is not set in GAM the
operator will be prompted to enter a pipe diameter.
In order to use the anemometer it is important to know the internal diameter (ID) of the
pipe if you want to understand the flow in m
3
/hr (metres cubed per hour). This must be
the internal diameter not the outer diameter (OD) i.e. pipe outer diameter minus twice the
pipe wall thickness.
For Example:
The anemometer is run by a 9v battery. If the anemometer is not being detected by the
analyser check the battery.
Note:
Please ensure that the anemometer battery pack is kept dry. For protection
against wet, damp conditions, it is recommended that the battery pack is
placed in the soft carry case back pocket.
If you do not have any suitable monitoring points you will need to drill a hole in the piping
of between 25mm and 30mm in diameter to seat the conical fitting on the anemometer
(which is roughly between 20mm to 34mm). When not in use the hole can be filled with a
bung.
Pipe ID
Pipe OD
Wall Thickness
Battery Pack
Anemometer
