GeoDesy GD-P1000E1000 - Manual (Page 9)

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GeoDesy Kft. Telefon: 06-1-481-2050
H-1116 Budapest, Kondorfa str. 6-8. Fax.: 06-1-481-2049
E-mail: [email protected]
http://www.geodesy.hu
3 Sites of installation
3.1 Key factors of operation
There are four key issues that the site survey has to shed light on. Proper system
operation cannot be guaranteed without satisfying all of the four requirements.
Clear line of sight - The entire optical path between the two ends must be free of
any obstacles. It not only means that one has to see the other side, but other
possible sources of disturbance should also be taken into consideration. For example
there might be turbulence above the roofs and other constructions, and this can
cause fraction or scattering of the beam or snow accumulation on roofs too close to
the beam can influence or even interrupt communication.
Solid mount surface - is the key for long-term operation. Since the diameter of
the beam is limited, it is extremely important to mount the unit on a stable structure
with the possible smallest movement. This way the receiver of the remote unit cannot
get out of the beam due to the movement of the opposite head.
East-West orientation - although the receiver optics are equipped with optical
filters to protect the receiver diode from the effect of undesired light sources, direct
sunshine can cause saturation of the diode. This prevents the system from working
properly for several minutes a day at certain times of the year. In most cases this
effect can be avoided by careful selection of the mounting spot.
In order to comply with the requirements of the successful installation - including the
discussed four key factors and other criteria - the following matters should be taken
into consideration.
3.2 Preferred installation sites
All buildings and constructions have a certain movement of their own. It’s determined
by the structure and material of the building. Metal structures can shift or twist due to
temperature changes. Wooden construction can expand or shrink with any changes
in humidity. Give preference to concrete or brick buildings. On the other hand high
structures like towers, skyscrapers or poles are always subject to movement. Mount
the support frame to walls of the building or near corners, as they are the most stable
spots. Use appropriate consoles for wall mounting. If a stand is used on the top of
building, secure it directly to the ceiling or to the concrete cornice wherever is
possible. Do not fix stands to insulating materials as they can slowly sink under the
weight of the unit and with temperature changes. Big chimneys and smokestacks
may look stable, but as their inner temperature varies they can also move. Vibration
caused by heavy traffic, trains and elevators etc. may slowly move the system out of
its specified direction. Another important consideration is to provide enough space for
alignment and to have the potential for future maintenance. Consider that the support
frame is usually heavy, so the selected spot should be easily accessible.