Chapter 4 - Post-Installation Activities
4.1 Troubleshooting Your Installation
It is normal to see noise spikes in the horizontal channels of a Trillium Compact seismometer
as the instrument settles after installation. However, if these spikes do not diminish after a
few days, there may be a problem with the installation and the site should be visited to
determine the cause of the spikes.
The following tables list common types of noise that may occur and the reasons why the noise
may be present.
Noise Type
Possible Cause
Spikes on horizontal channels
l
There is a force pulling on the cable.
l
There is unstable soil around the seismometer. Note that
deploying in unstable soil may be a deliberate choice for a
posthole installation if that is the only way to place a
seismometer at that location, for example a marsh or flood
plain.
Continuous low frequency
wander (random noise, larger on
horizontal channels)
l
The hole is not sealed and air drafts are causing
temperature fluctuations.
Spikes on the vertical channel
l
Usually due to electrical system noise. For example, power
supply noise from a battery charging circuit, or interference
from a strong magnetic or radio source that is nearby.
Table 4-1 -
Types of noise and possible causes for posthole deployments
Chapter 4 - Post-Installation Activities
16889R10 • 2020-11-12
Page 49
Содержание Trillium Compact
Страница 1: ...User Guide November 12 2020 Strategic Intelligence Fueled by Science...
Страница 76: ...Figure 10 2 Noise floor figure for 120 s models Chapter 10 Performance 16889R10 2020 11 12 Page 76...
Страница 78: ...Figure 10 4 Trillium Compact seismometer performance Chapter 10 Performance 16889R10 2020 11 12 Page 78...
Страница 83: ...Figure 12 2 Bottom view Figure 12 3 Side view Chapter 12 Features and Dimensions 16889R10 2020 11 12 Page 83...
Страница 85: ...Figure 12 6 Side view Chapter 12 Features and Dimensions 16889R10 2020 11 12 Page 85...
Страница 95: ...Figure C 1 Cut away illustration of a packed carrying case Appendix C Carrying Case 16889R10 2020 11 12 Page 95...