Vibratory Tachometer - Adjust
SMCS Code: 7462-025
Drum Vibration Tachometer
To avoid damage to the vibratory system during testing,
always perform the testing with the vibratory drum on top
of tires or on loose dirt. Tires will simulate a non-
compacted soil condition.
Never operate the vibratory system when the machine is
If a testing time longer than three (3) minutes is required,
rotate the drum periodically in order to lubricate the
eccentric weight shaft bearings.
(1) Vibratory on/off control. (2) Vibratory amplitude control.
NOTE: The hydraulic oil temperature should be at least
38° C (100° F).
Make sure that the parking brake is applied. Ensure
that the propel control lever is in the STOP position.
Move the vibratory amplitude control (2) to the HIGH
Start the engine. Run the engine at high idle. Engine
speed should be 2350 ± 50 rpm.
(3) Vibratory tachometer
Depress the vibratory on/off control (1) on the control
console to the ON position. Read the vibrations per
minute (VPM) from optional VPM gauge (3).
End of Drum
(4) Drum vibration tachometer.
Read the VPM from 133-0963
Tachometer (4) or the 133-9905 Frequency Meter.
Compare these values with the reading from the
optional VPM gauge (3).
VPM gauge (3) must be calibrated if the values are not