© PCE Instruments
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The vibration calibrator PCE-VC20 generates mechanical vibrations with quartz stabilized
frequency and precisely controlled magnitude. Vibration sensor, including connected cables,
signal conditioners and readout instruments can be calibrated in acceleration, velocity or
displacement units.
A reference accelerometer inside the shaker head and a control circuit keep the vibration level
constant and independent of the weight of the attached measuring object. A display indicates
the error in percent. There is an acoustical warning when the error limit is exceeded.
Because of its internal rechargeable battery, the PCE-VC20 is well suited for mobile application.
The instrument features an automatic switch-off function preventing accidental discharging. The
display indicates the battery charging condition. The unit comes with an external mains supply
for charging.
The supplied plastic carrying case allows convenient handling and safe transport.
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Operation
6.1
Attaching the Test Object
The Vibration exciter of the PCE-VC20 has a tapped M5 hole with 7 mm depth for the
attachment of the device under test. The supplied stud bolts and stud adapters or a clamping
magnet can be used for mounting.
The surface of the vibration exciter has made extremely resistant by plasma nitride coasting.
For light transducers, adhesive wax or double sided adhesive tape can be used for mounting. A
flat surface for adhesive mounting can be obtained by using the M5 insulating flange Model 029
which is available from Metra.
Magnetic and adhesive attachments are only allowable for roughly estimated calibrations.
Accuracy is only guaranteed for screw attachment.
When mounting the specimen, pay attention to the symmetrical distribution of the object weight.
Otherwise, the vibrating system may be deflected from its main axis. When using coupling
structures for calibration of transducers, symmetrical attachment becomes especially important,
for instance, at the calibration of the x and y axis of a triaxial accelerometer. In the case, using a
balance weight as shown in the following illustration is recommended.
