4 installing in vaults – Guralp Systems CMG-6TD User Manual

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Installing the 6TD

4.4

Installing in vaults

You can install a 6TD in an existing seismic vault with the following

procedure:

1. Unpack the sensors from their 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.

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.