CEMB USA C72_2 (A) - Manual (Page 27)

I 0459 - 27 GB
Err. 20 Wheel at standstill. The wheel is at a standstill for
more than one second after START.
1. Check functioning of the phase generator.
2. Check the connections on the power board.
3. Replace the computer board.
Err. 24 Distance between the spokes smaller
than 18 degrees.
1. The minimum distance between the spokes where to split the
unbalance must be greater than 18 degrees
2. Repeat the SPLIT function increasing the distance between the
spokes.
Err. 25 Distance between the spokes greater
than 120 degree
1. The minimum distance between the spokes where to split the
unbalance must be smaller than 120 degrees
2. Repeat the SPLIT function increasing the distance between the
spokes.
Err.54 Sonar readout error.
Sonar value readout impossible.
1. Position the eccentricity measurement sonar correctly before
performing the measurement.
2. Check eccentricity sonar connections.
3. Check the power supplies on the power card.
4. Replace the eccentricity measurement sonar.
5. Make sure that the wheel does not halt before completing at least
4/5 revolutions after the first braking impulse.
6. Verify belt tautness.
7. Replace the computer board.
Err.55 Sonar readout error.
Sonar values are insufficient for correct measurement
of eccentricity.
1. Position the eccentricity measurement sonar correctly before
performing the measurement.
2. Make sure that the wheel does not halt before completing at least
4/5 revolutions after the first braking impulse.
3. Verify belt tautness.
4. Mount a wheel of medium dimensions (14”x5 ¾”) and perform an
eccentricity measurement . If in these conditions error 55 no longer
occurs, this means that the wheel inertia causing the problem is
such as to half the wheel before having acquired the minimum
number of values necessary for reliable eccentricity measurement.
7.1 - Inconsistent unbalance readings
Sometimes after balancing a wheel and removing it from the balancing machine, it is found that, upon mounting it on
the machine again, the wheel is not balanced.
This does not depend on incorrect indication of the machine, but only on faulty mounting of the wheel on the adapter;
i.e. in the two mountings, the wheel has assumed a different position with respect to the balancing machine shaft
centre line. If the wheel has been mounted on the adapter with screws, it could be possible that the screws have not
been correctly tightened, i.e. crosswise one by one, or else (as often occurs) holes have been drilled on the wheel
with too wide tolerances.
Small errors, up to 10 grams (0.4 oz) are to be considered normal in wheels locked by a cone; the error is normally
greater for wheels fastened with screws or studs.
If, after balancing, the wheel is found to be still out-of-balance when refitted on the vehicle, this could be due to
the unbalance of the car brake drum or very often due to the holes for the screws on the rim and drum sometimes
drilled with too wide tolerances. In such case a readjustment could be advisable using the balancing machine with
the wheel mounted.
8 - Routine maintenance
Switch off the machine from the mains before carrying out any operation.
8.1 - To replace the fuses
The power supply board, accessible from the rear by removing the rear cover, is fitted with safety fuses (see
Exploded Drawings). If fuses require replacement, use ones of the same current rating.
If the fault persists, contact the Technical Service Department.
NONE OF THE OTHER MACHINE PARTS REQUIRE MAINTENANCE.