Guralp Systems CMG-5TD - Manual (Page 13)

CMG-5TD Digital Accelerometer Operation
5 Operation
5.1 Installation overview
These steps make up the installation procedure. Detailed instructions follow
in subsequent sections.
•
Unpack the accelerometer system from the reusable container (See
quick start). Save the shipping box for possible future use.
•
Prepare the mounting surface.
•
Mount the levelling baseplate to the CMG-5TD.
•
Orient the CMG-5TD using the orientation pointers.
•
Anchor the baseplate to the mounting surface.
•
Level the CMG-5TD.
•
Install the GPS receiver providing a clear view of the sky, and connect
it to the CMG-5TD using the GPS cable.
•
Connect the CMG-5TD to a PC running Scream
•
Connect the power supply (12 to 36 V DC) to the grey/blue power/data
cable
•
Switch on the power and view the acceleration time series using
Scream.
•
Using a DVM, check and adjust the CMG-5TD offsets if required.
•
Cover the sensor with a polystyrene cover for long term thermal
stability. The cover will act as a thermal shield from draughts.
Position the polystyrene box carefully so that it does not touch the
sensor package.
5.2 Installation method
The surface should have a scribed north/south orientation line accurately
surveyed from reliable markers. Mount the concrete anchor into the
mounting bench, around the middle of the orientation line. Loosely attach
the mounting (lower) portion of the levelling plate to the concrete anchor,
using the bolt provided. Attach the upper portion of the levelling plate to the
base of the CMG-5TD using the screws provided. Finally, attach the CMG-5TD
to the mounting base by joining the two portions of the levelling plate using
the socket-cap screws provided.
MAN-050-0005 13 Issue D - April 2013