CEMB USA ER80 (B) - Manual (Page 19)

19
Use and maintenance manual Rev. 10-2011
ENGLISH
7. Diagnostics
7.1 INCONSISTENT UNBALANCE
READINGS
In some cases, when a wheel that has just been balanced
is repositioned on the balancer, the machine can detect
an unbalance.
This is not a machine problem but is due to faulty mounting
of the wheel on the flange. In other words, when mount-
ing the wheel after initial balancing, it has taken another
position with respect to the balancer shaft axis.
If the wheel has been mounted on the flange with screws,
the screws may not have been tightened correctly (criss-
cross sequence) or the tolerances of the holes drilled in
the wheel may be too large. Small errors, up to 10 grams
(0.4 oz), are to be considered normal in wheels locked
with the relative cone: The error is normally greater for
wheels locked with screws or studs.
If, after balancing, the wheel is still unbalanced when re-
fitted on the vehicle, this could be due to an unbalanced
brake drum or, very often, the tolerances of the holes
drilled in the rim and drum are too large. In this case,
balancing should be performed using a balancer with the
wheel mounted on the vehicle.
7.2 ALARM SIGNAL
The machine has a self-diagnostics cycle which identi-
fies the most frequent malfunctions during the normal
work cycle.
These malfunctions are processed by the system and
shown on the display.
Diagnostics