Accelerometers
for the measurement of acceleration, shock or vibration come in
many types using different principles of operation.
Inside a piezoelectric version, the sensing
element is a crystal which has the property of emitting a charge
when subjected to a compressive force.
In the accelerometer, this crystal is
bonded to a mass such that when the accelerometer is subjected
to a 'g' force, the mass compresses the crystal which emits a
signal. This signal value can be related to the imposed 'g'
force.
The sensing element is housed in a
suitable sensor body to withstand the environmental conditions
of the particular application. Body are usually made in
stainless steel with welding of the various parts to prevent the
ingress of dust, water, etc.
Electrical connection can be via a sealed
cable or a plug/socket arrangement.
Many present accelerometers have internal
electronic circuitry to give outputs which can be directed used
by the associated acquisition or control systems.
Mechanical fixing of the sensor is
important in order to achieve true transfer of the vibration or
acceleration. Many fixing methods are used including beeswax,
hard glues, threaded stud (male or female), magnetic mounts.
Accelerometers are used in many scientific
and industrial applications such as predictive maintenance,
aerospace, automotive, medical, process control, etc
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