58
Ver. 04-2015
Use and Maintenance Manual
ENGLISH
Setup
BPC (Best Possible Correction) Provides the best possible solution for reduction of vibrations noticeable
in the vehicle.
Many elements affect the vibration perceived in the vehicle due to wheel unbalances:
• Residual static unbalance
• Residual dynamic (or torque) unbalance
• Wheel weight (the heavier the wheel, the less the unbalance will make it vibrate)
• Wheel diameter (on which the application radiuses of the counterweights depend)
Comparison between conventional balancing and the BPC method
CONVENTIONAL BALANCING:
▪
Given a set tolerance of 5g, a wheel is considered balanced also with a residual unbalance of 4.9g per
plane in approximately the same angular position. This means that a static unbalance of 9.8 grams is
tolerated, even though the static unbalance is deemed the main cause of vibrations noticeable by the
driver.
▪
The balancing tolerance for all wheel types, not taking any unbalance of 10g into account, produces
different vibrations on a 13” or a 22" wheel. The residual vibrations are inversely proportional to the
wheel weight.
▪
The angular position of the residual unbalances is not taken into account.
BALANCING USING THE BPC METHOD:
▪
With this method, the balancing tolerance value is reprocessed based on the wheel dimensions and
the permissible residual static and torque unbalances, which are numerically different (greater torque
unbalance than static unbalance is permitted).
▪
The tolerance no longer refers to the correction planes but is UNIQUE and indicates the residual vibration
limit value permissible on the wheel.
▪
An indicator on the screen provides information on the residual vibration obtained after balancing with
respect to the maximum tolerable vibration.
▪
Bymeans of complex mathematical calculations, it indicates how many and where correction weights
should be added for the best possible reduction of the vibrations noticeable by the driver. This means
that the customer receives the best possible service.
No alternative method can be more accurate, using moderate weights with steps of 5g.
The machine also measures by HOW MUCH the “noticeable vibration” in the vehicle has been reduced
with respect to the conventional method, indicating the percentage reduction, i.e. by how much it has
improved with respect to conventional machines.
Less vibration, more satisfied customers!
Display pitch:
this represents the unbalance display pitch and varies based on the unit of measure
selected. Selecting 5g (1/4 oz) enables display of the correction values on the two sides
such as to set the static unbalance value to 0 (theoretical).
It is advisable to set this function for normal use of the machine, as it improves the balancing
quality. The computer makes a complex calculation which allows cancelling the residual
static unbalance by varying the value and the position of the counterweights fixed in steps
of 5 grams (1/4 oz).
Tolerance
:
this is the unbalance threshold below which OK appears on the screen instead
of the unbalance value at the end of the spin.
Default parameter setting:
resets the default machine settings.
