Nanometrics TC120-PH1, Руководство пользователя

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Chapter 3

Performing a Surface Vault Installation
Trillium Compact User Guide
16889R5

2014-03-04
19
Figure 3-2 shows the case-top north-south guide with a dashed line indicating where a
straight-edge, staked line, or laser level line would fall.
Figure 3-2 Example of seismometer alignment using the case-top guide
3.5 Best Practices for Alignment and Levelling
Following are best practices for aligning and levelling a Trillium Compact using the
vertically scribed marks on the north-south axis or the north-south guide on the top of the
case:

Prepare the north-south guideline using one of the following methods:
a) Using the north-south vertically scribed marks: Draw a line on the installation surface
parallel to north-south.
b) Using the case-top north-south guide: Stake a line (for example, using fishing line)
parallel to north-south, directly over the location where you want to install the
Trillium Compact.
The north-south line must be aligned to true north. If you are using a magnetic
compass, account for the local magnetic declination when drawing the line. For
underground installations, you can transfer north measured at the surface to below
ground by traversing with survey equipment.
The seismometer in Figure 3-2 illustrates model numbers TC120-SV1 and TC20-SV1, but it is also
applicable to model numbers TC120-PH1 and TC20-PH1 (stainless steel enclosure).
Straight-edge, staked
line, or laser level line
North-south guide
N