HUATEC Group Corporation www.huatecgroup.com
P a g e 8 o f 3 7
3 BALANCING PREPARATION
Before using HG904 for balancing, the following must be done firstly:
<1>
Confirm Dynamic Balance Needed
Affirm that machine has fault of imbalance and that it can be eliminated by the
method of balancing. Once the machine has heavy vibration, we should do frequency
analysis with the vibration signals firstly. Generally, the probability of imbalance is
higher. So, when the vibration includes a high rotation-frequency spectrum peak and
less harmonic frequency peak, meantime without evidence of other faults, very
possible it is the fault of imbalance.
<2>
Mount Sensors
Vibration Sensors
: It should be disposed in the horizontal direction (or vertical if
horizontal not possible) on the bearing base, or on the base frame. Because dynamic
balance is vector calculus, the position and direction of the sensor should keep
unchanged in the balancing process.
Photoelectric sensors
: Paste a reflecting or unreflecting adhesive paper (according
to the condition
of the rotor’s surface) to a visible place of the rotor or its axis.
Photoelectric sensor can give HG904 1 electric pulse per turn of the running rotor.
Not only the rotate speed can be measured but also the vibration signals can be
compared with pulse signals. So the phase of the rotation-frequency vibration can be
obtained. During the balancing process, the position of the reflecting adhesive paper,
the position and direction of the photoelectric sensor should keep unchanged.
<3>
Connect Sensor Cables
The photoelectric sensor should be connected to the Tacho/Trigger socket of
HG904
.
For 1-plane balancing, 1 vibration sensor should be connected to the Accelerometer
Channel A or Voltage Channel A socket. For 2-plane balancing, a second
accelerometer should be connected to the Accelerometer Channel B or Voltage
Channel B socket.
<4>
Start Machine
Start the machine and wait till it reaches its normal rotation speed (could be
measured with the RPM measurement function).
NOTICE:
1
Because of the strong pull force of the magnetic mount, when remove the
sensor from the measurement surface, use your hand carefully. Do not
remove the sensor by dragging the cables.
2
Before measurement, the sensitivity of the sensors must be inputted to
HG904 correctly.
3
The
internal/external
trigger switch should be set to “external”.