Detect Landslides

When the Select-Alarm is used with a vibration sensor mounted on a ground stake, it can detect the early signs of a developing landslide. The United States Geological Survey, See (USGS), Federal Emergency Management Agency, See (FEMA) and Centers for Disease Control, See (CDC) websites report lots of warnings signs before a landslide occurs. All of these warning signs involve small movements and vibrations in the ground. See (MUD, ROCK, LANDSLIDES).

It can also detect extremely weak vibrations from other dangerous local sources such as Rockslides, Mudslides, Flash Floods, Tsunamis, Earthquakes, Volcanoes and Tornadoes touching the ground.

This is the mode recommended for homeowners. In this display the scope shows a rambling and noisy signal from the 3D vibration sensor and the signal level bar graph shows an extremely strong signal level. A signal level of this magnitude would only be seen in extreme and dangerous conditions.

When the signal level first turns red, it’s a sign that a landslide might be developing. If it continues, evacuate immediately.

To set the system up to detect dangerous ground vibrations from local sources, first, take note of the level on the SIGNAL LEVEL bar graph, then go to the OPTIONS page. Ensure that the ALARM IS ENABLED, then go to FAST AGC (Automatic Gain Control). FAST AGC will appear in the CURRENT AGC SETTINGS window. Then go to INFRASIGNAL ON CHART or GO BACK TO MODE >> ADJUSTMENTS and adjust the red ALARM threshold to just above the signal level you took note of on the SIGNAL LEVEL bar graph. Then go back to the INFRASIGNAL ON CHART or SCOPE. The alarm threshold is shown numerically and by the two red markers, one on each side of the green/yellow/red signal level bar graph. This may require several tries (ADJUSTMENTS page – MODE page – ADJUSTMENTS page etc.) before reaching the “no faults alarms” level.

If the alarm is too loud for you, touch the TEST ALARM button >> ALARM 10% VOLUME >> ALARM RESET.

If you get short burst of vibrations occasionally, try to identify the source and determine if they are benign. If they are not dangerous, the settings may be better if you set OPTIONS >> NORMAL AGC >> INFRASIGNAL ON CHART or GO BACK TO MODE and don’t use the FAST AGC option.

Every location and installation are different, so only local trial and error can determine the proper adjustments and settings to prevent faults alarms and yet be sensitive enough to detect very early rumbling of dangerous ground vibrations.