Do not apply any undue stress to the machine
during wheel spin to obtain the most accurate
results.
- Wait for the wheel to stop automatically and for
the calculated unbalance values to be displayed.
- Select the first side to be balanced.
- Turn the wheel until the central element of the
corresponding position indicator lights up.
- Apply the indicated balancing weight in the
position on the rim corresponding to 12 o'clock.
- Repeat the operations listed above for the
second side of the wheel.
- Perform a test wheel spin to check the balanc-
ing accuracy. If it is not considered satisfactory,
change the value and position of the previously
applied weights, according to the data indicated
in the balancing control diagram (fig.21).
Bear in mind that a counterweight positioning error
of just a few degrees may lead to a residual unbal-
ance as large as 5-10 grams during the verification
phase, especially in the case of large unbalances.
Press the
button to activate the wheel-
holder shaft locking brake. This procedure makes
the balancing weight application easier.
The wheel is released by pressing the same but-
ton again, by performing a new balancing spin or
after about 30 seconds.
The shaft locking system can also be useful dur-
ing installation of special centring accessories.
WARNING
Check that the system which fits the weight to
the rim is in optimum condition.
A weight which is not fitted properly or correctly
EM 9550 - Operator's manual
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1
21
may come off as the wheel rotates, thus creating
a potential danger.
Pressing the
is moving interrupts the wheel spin before time
and the A STP message is displayed.
If the "RPA" (centred position) programme is ac-
tive, at the end of each balancing spin the machine
stops the wheel in the position for application of
the weight on the inner side; if it is equal to zero,
the wheel is stopped in the position for applica-
tion on the outer side.
Pressing the
raised, automatic search for the second side
position is activated.
This function is described at length in the AUTO-
MATIC POSITION SEARCH section.
Static balancing
A wheel can be balanced using a single counter-
weight on one of its two sides or in the centre of
the well. In this case, the wheel is balanced stati-
cally. However, there is still the risk of dynamic
unbalance, which becomes more significant as
the width of the wheel increases.
Proceed as follows to balance a wheel in static
mode:
- Set the wheel's geometric data as described in
the "WHEEL DATA ENTRY" chapter.
- Spin the wheel by lowering the guard;
- wait for the wheel to stop automatically and for
the calculated unbalance value to be displayed;
- Press the
button.
- the message STATIC will be displayed in the
status line on the LCD display.
- rotate the wheel until the central element of
the position indicator lights up;
- apply the balancing weight in the 12 o'clock
position on either the outer or inner side, or at
the centre of the rim well, indifferently. If applied
in the well, the weight is applied on a diameter
smaller than the rated diameter of the rim. A
value of 2 or 3 inches less than the rated value
must therefore be entered when the diameter
is set in order to obtain correct results;
- follow the instructions specified in the dynamic
balancing procedure to perform a test wheel
spin.
button while the wheel
button with the guard
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