Used to measure acceleration, probably the world’s largest selection of both piezoelectric accelerometer types charge mode and IEPE and DC accelerometers which work from 0 Hz and are relative to gravitational pull. Cable assemblies, mounting blocks, signal conditioners and amplifiers are readily available for both the piezoelectric accelerometers both charge mode and IEPE and the gravitational pull DC types.
Applications include Crash, Research & Development, Rail, Military/Aerospace, Automotive testing and Industrial applications.
Options include single axis accelerometers to trixial axis accelerometers with a wide range of supply voltages to measure acceleration.
All sensors incorporate the latest technologies whether this be the latest 6-inch wafer MEMs technology for the gravitational pull DC types, or shear mode clamping systems for the charge mode or IEPE piezoelectric accelerometers.
Incorporated brands include Measurement Specialties, TE Connectivity, IC Sensors, FGP, ATEX sensors and Entran.
An accelerometer measures the vibration or acceleration of motion from a structure. The force produced by the change in motion causes the mass to squeeze the piezoelectric strands. These stands will produce electrical charge proportionally to the amount of force exerted onto them.
Types of Accelerometers
There are two main type of accelerometers, low impedance and high impedance.
In a high impedance accelerometer, the electrical charge from the piezoelectric material is connected directly with a measurement instrument. Outputting the charge from this type of accelerometer requires instruments normally only found in research facilities.
A low impedance accelerometer works almost the same as the high impedance accelerometer, except it has a built-in transistor to convert the electrical charge to a voltage that is suitable for more common instrumentation.
Properties of an Accelerometers
The dynamic range of an accelerometer is the minimum and maximum amplitudes that the accelerometer can measure.
Frequency response is set by the mass, the piezoelectric properties and the resonance frequency. It is the frequency range where the output of the accelerometer is within a specified deviation, generally around 5% G.
The high frequency limit is the frequency where the output exceeds the stated output deviation. Low frequency cut-off is when the frequency goes below the stated accuracy and the sensitivity decreases.
Electronic noise is produced by the amplifying circuit. Noise typically decreases as frequency increases. The resonance frequency is the frequency at which the sensor rings or ‘resonates’. Frequency measurements should always be below the resonance frequency.
Sensitivity is the voltage that is outputted. Low output accelerometers are used to measure high vibration levels, whilst high output accelerometers are used for measuring low levels of vibration.