Nanometrics Trillium Compact, Руководство пользователя

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3.7 Aligning and Leveling a Trillium Compact in a Vault
Installation
Following are best practices for aligning and leveling a Trillium Compact Vault using the
vertically scribed markson the north-south axis or the north-south guide on the top of the
case:
1. Prepare the north-south guideline using one of the following methods. 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.
l
Using the north-south vertically scribed marks . Draw a line on the
installation surface parallel to north-south.
l
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.
2. When you are ready to remove the Trillium Compact Vault from the box, gently place it
on the installation surface in an approximate north-south alignment.
If you are using the optional leveling cradle, you will not be leveling the seismometer
using the leveling feet as described in the next step. Instead, see "Using the Leveling
Cradle" on page 96 , or if you are using the leveling cradle with its optional spike kit, see
"Using the Leveling Cradle and Spike Kit" on page 97 .
3. Use the adjustable feet, as required, and the leveling bubble placed on the cover to level
the seismometer. Center the bubble as precisely as possible inside the black ring to
ensure that the Z output is measuring true vertical motion:
a. Extend the leveling feet as little as possible to achieve a level seismometer. Try to
keep one of the feet fully retracted into the seismometer base for greatest
stability.
b. When the Trillium Compact Vault is level, lock each foot using a 2.5 mm Allen key,
by inserting Allen key into one of the lock nut holes and turning the lock nut until
it engages firmly with the base of the seismometer. A foot that is properly locked
will not turn easily when touched.
Chapter 3 - Installing a Trillium Compact Vault Seismometer
16889R10 • 2020-11-12 Page 39