Guralp Systems CMG-6T - Manual (Page 13)

Operator's Guide
1. Unpack the sensor from its container, saving the shipping boxes
for later transportation.
2. Prepare the mounting surface, which should be smooth and free
of cracks. Remove any loose particles or dust, and any pieces of
loose surfacing. This ensures good contact between the
instrument's feet and the surface.
3. If it is not already present, inscribe an accurate North-South line
on the mounting surface.
4. Place the sensor over the scribed line, so that the brass and steel
pointers are aligned with the marked directions, with the brass
pointer facing North. This can be done by rotating the base of
the sensor whilst observing it from above. The brass pointer can
be found next to one of the feet.
5. If you cannot easily see the pointers, you should align the
sensor using the north arrow on the handle. However, the
alignment of the handle with the sensors inside is less accurate
than the metal pointers, so they should be used wherever
possible.
6. The top panel of the CMG-6T includes a spirit level.
Level the sensor using each of the adjustable feet of the
instrument in turn, until the bubble in the spirit level lies
entirely within the inner circle. (The instrument can operate
with up to 2 ° of tilt, but with reduced performance.)
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