Rion VM-83, Instruction Manual, Page: 84 / 106

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Technical Information
Accelerometer installation
The accelerometer can be mounted to the measurement object in one of the
four general ways outlined below. The accelerometer mounting method greatly
affects the contact resonance frequency *. The advantages and disadvantages
of various methods are described in this section.
Rigid screw mounting
This mounting principle assures optimum frequency response
characteristics. The mounting surface should be perfectly
smooth, and the screw holes (M6) must be drilled in such a
way so as not to disturb perpendicularity of the accelerometer.
Insulation attachment mounting
This mounting principle is used when electrical insulation
between accelerometer and measurement object is required.
The contact resonance frequency will be lower than with
rigid screw mounting. Regarding the screw holes, the same
precautions as for rigid screw mounting apply.
Magnet attachment mounting
Because the contact resonance frequency will be quite low, this
principle is mainly suited for vibration measurements in the
medium to low frequency range. The maximum acceleration
that can be measured depends on the accelerometer mass.
Rod attachment mounting
Pressing the accelerometer against the measurement object
with a rod is the simplest method, but the measurement fre-
quency range would be about several hundred Hz, because the
contact resonance frequency will be very low. This method
should only be used if the other three mounting methods are
not feasible.
Note
Tighten the M6 screw fi rst on the piezoelectric ac-
celerometer side and then mount the rod attachment.