Multisensor Placement For Earthquake Detection - Motorola MC4000 Quick Start Manual

MultiSensor placement for earthquake detection

The accelerometer sensor is designed to detect shaking motions
typical of earthquakes that continue for about a second or more. If
you want to monitor earth vibrations including earthquakes, the
MultiSensor should be mounted to a building foundation (such as a
basement wall). Any other placement can result in acceleration
reports that reflect vibrations from sources ranging from footsteps, to
mechanical vibrations in the home (blower and circulator motors,
appliances, plumbing, and many more), to environmental conditions
like gusty winds. For best results, orient as precisely vertical or
horizontal as possible.
Note that even when mounted to a basement wall, the MultiSensor
acceleration reports may deviate significantly from true scientific
measurements for various reasons including subsoil conditions under
the foundation, or because the MultiSensor isn't truly isolated from
equipment in the basement. For example, if the MultiSensor shares a
power receptacle with a washer, dryer or dehumidifier, the
MultiSensor may detect vibrations transmitted through the appliance's
electrical cord.
When you configure accelerometer alerts, you can set a threshold for
the minimum acceleration for which you want to receive alerts. When
an accelerometer alert is set, the device will not report or keep a
history of any shaking events below the threshold level. When no
accelerometer alert is set, the MultiSensor will keep a history of all
shaking events that it detects, regardless of the threshold setting. The
minimum detectable level is sensor reading 4.
Additional information is available online at
www.motorolanetwork.com/SensorInfo
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