Accu-Turn 1250, Руководство по обслуживанию, Страница: 75 / 85

M 0496 GB - 12
l
d I
d E
a
b
Resting surface
9 - WHEEL MEASUREMENT AND PRESETTINGS
ON THE BALANCING MACHINE
The ever increasing need for more accurate calibration and use of the ALU functions means that it is important to esta-
blish how to measure the rims and how the balancing machine interprets the preset data. Hence a description is now
given of how to modify the preset dimensions automatically in order to obtain the distances of the correction planes
which are defined as through planes for the centres of gravity of the corrective weights. Consider a typical rim: size “
l
”,
given as width by the rim manufacturer, differs from the measurement of the distance between the correction planes for
the rim thickness and physical dimensions of the counterweight, whose centre of gravity is located at distance “h” from
the resting point of the rim edge. The balancing machine automatically corrects the measurement preset by adding 2 x
h = 6 mm to the measurement. Measurement “b” made with the gauge is generally more accurate even if very similar
to the measurement “
l
” known to the rim user. The two measurements differ only by the thickness of the sheet metal,
usually about 2 mm per side. Such insignificant distance means that an accurate calibration can be obtained regard-
less of whether the inner rim with “
l
” or outher width “b” is preset. It is a good rule to add ¼ inch to the value given by
the manufacturer. As regards the ALU functions, the machine performs the following approximations in addition to the
systematic correction regarding the centre of gravity of the counterweight as seen above.
ALU 1
a = a ¾”
b = b preset - 1 ½”
d = d preset - 1”
ALU 2
a = a ¾”
b = distance of adapter surface -½”- a
dI = d preset - 1”
dE = d preset - 2 ½”
ALU 3
a = a preset
b = distance of adapter surface -½”- a
dI = d preset
dE = d preset - 2 ½”
ALU 4
a = a preset
b = b preset - 3/4”
dI = d preset
dE = d preset - 1”
ALU M
a = a preset - 8 mm por automovil
a = a preset - 10 mm por camion
b = b preset - a
dl = d preset
dE = dI - 1”
NOTE : I = INSIDE
E = OUTSIDE
N.B.: ALU1/2/3/4 can only be selected if the wheel balancer is set to vehicle mode.