Honda G100K2 Applications Manual page 31

VIBRATION
FREQUENCY PICK-UP
Many different kinds of pick-ups are available, although only two types: the electrokinetic (velocity type) pick-up and
the piezoelectric (acceleration type) pick-up are most commonly used because of their outstanding ease of use and
stability.
The piezoelectric pick-up is most commonly used for measuring vibration acceleration of automobiles and engines.
Important notes to remember:
•
Align the direction of vibration of the pick-up with that of the vibrator.
•
Select a pick-up which is as light as possible compared to the weight
of the item being measured. If the pick-up is too heavy, its weight itself
will act as a mass damper.
VIBRATION MEASURING METHOD
Install the piezo-electric acceleration pick-up on the engine
mount base at the center position of the engine mount bolts.
* mount base can be crankcase cover or flange in case of
engine direct mount to application (tamper, brushcutter).
Remove any dirt and oil from the measuring surface of the
engine and bond the pick-up with instant adhesive.
Use a handheld, digital display vibration meter and measure
the RMS or EQ Peak values along the three axis: vertical,
longitudinal and lateral at the entire engine rpm operating
range.
Vibration is measured with the low pass filter (500Hz)
switched ON.
Note
Be sure that old layers of adhesive are removed from the
pick-up; these layers can form an insulant for vibrations.
Removal of the pick-up can be easily done by inserting a
small screwdriver under the pick-up.
Tamper engine
* vibration
measuring
point
Flange for tamper
direct mounting
M4 engine
Measuring
Battery
point
Longitudinal
Vertical
Vertical shaft
engine
Measuring point
- 30 -
Z
Y
X
Vertical
Lateral
Horizontal
shaft engine
Measuring
point
Lateral
Longitudinal