Guralp Systems CMG-40T User Manual
Page 15
Operator's guide
In temporary installations, environmental factors are also important. The sensor
needs to be well protected against
•
fluctuations in temperature,
•
turbulent air flow around walls or trees, or around sharp corners or edges
in the immediate vicinity of the sensor;
•
vibration caused by heavy machinery (even at a distance), or by
overhead power lines.
This can be done by selecting a suitable site, and placing the instrument in a
protective enclosure. An open-sided box of 5 cm expanded polystyrene slabs,
placed over the instrument and taped down to exclude draughts, makes an
excellent thermal shield.
After installation, the instrument case and mounting surface will slowly return
to the local temperature, and settle in their positions. This will take around four
hours from the time installation is completed.
January 2006
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