Accu-Turn 1250 User manual

SERVICE
MANUAL
MODELS 1250, 1450, 1550, 1650, 1850

Model1250
WheelBalancer

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Special maintenance M
CONTENTS page
1 - CHANGING SUPPLY VOLTAGE ...................................................................................................................................3
2 - CHECKING OF THE RIM DISTANCE GAUGE .............................................................................................................3
3 - ASSEMBLY OF THE PIEZO MEASURERS ..................................................................................................................4
4 - LOGIC TROUBLE SHOOTING SEQUENCE ................................................................................................................5
5 - POWER SUPPLY LAYOUT DIAGRAM .......................................................................................................................6
6 - REPLACING THE POWER BOARD .............................................................................................................................7
7 - FUNCTION AND PRECISION CHECK .........................................................................................................................8
8 - WHEEL MEASUREMENT AND PRESETTINGS ON THE BALANCING MACHINE ................................................10

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1 - CHANGING SUPPLY VOLTAGE
(See recommended spare parts lists and power layout diagram)
The wheel balancer can operate at 115 V - 50/60 Hz or 230V - 50/60Hz.
To change the supply voltage, proceed as follows:
1) Replace the motor.
2) Replace the entire power board or else modify the board as follows:
A) Replace the capacitor
B) Replace the transformer.
2 - CHECKING OF THE RIM DISTANCE GAUGE
Check that the ruler used for measuring the DISTANCE of the wheels reads 21,5 cm as measurement of the distance
from the adapter plane. If the graduated scale is changed, position it with the line indicating 21,5 cm at the fixed limit
(reading point) when the gauge tip coincides with the adapter plane.
Reading point : 21,5 cm Adapter plane

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3 - ASSEMBLY OF THE PIEZO MEASURERS
Problems of excessive compensation and out-of-phase sometimes depend on a fault in the piezo measurers.
To replace them, proceed as follows:
1. Remove the weight shelf.
2. Remove nuts 1 and 2 with relative cup springs and washers.
3. Back-off screws 3, 4, 6 and 5 then disassemble the various parts.
4. Reassemble the various parts without tightening the nuts being careful to follow the correct sequence.
N.B.: Mount the piezo units in accordance with the position of the coloured wires shown in the drawing.
5. Keeping the spindle perfectly aligned, tighten the nuts 5 and 6 with a spanner, and nuts 3 and 4 by hand (by half a
turn with the spanner if necessary).
6. Refit the washers, cup springs and nuts 1 and 2. Tighten the nuts fully in order to fully regain the elasticity of the cup
springs, then loosen them by half a turn. This will automatically ensure correct preloading on the piezo (a torque
wrench can be used set to 400 kg. cm.).
7. Cover the piezo units with a generous layer of silicone.(N.B.: For correct operation, insulation of the piezo
crystals should be greater than 50 Mohm).
8. Reassemble the various parts.
9. Again carry out the automatic calibration.
yellow
blue
yellow
white

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4 - LOGIC TROUBLE SHOOTING SEQUENCE
Is the fuse on the computer board
in a good state?
NO
YES
Replace the computer board
Replace the fuse and switch on
Is the fuse working?
Disconnet CN1 on the power board.
Again replace the fuse and switch on.
Is the fuse working?
Does the voltage across
points 3-4 on the transformer
connector correspond to that
shown in the layout diagram?
YES
Check that the transformer primary be
energized with the mains voltage and
that there is not damage in the wiring.
If everything is OK, replace the transfor-
mer.
YES
NO
Is the position sensor working?
(see SELF DIAGNOSTICS)
Replace the position
sensor board.
NOTE : Do not remove
the mounting brackets.
Replace the computer board
YES
NO
NO
YES
Replace the power
board
Is the fuse working?
NO

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5 - POWER SUPPLY LAYOUT DIAGRAM
( 230 V connection )

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6 - REPLACING THE POWER BOARD
( check voltage )

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7 - FUNCTION AND PRECISION CHECK
If faults or inaccuracies are encountered which are not readily identified, it may be useful to perform the function and
precision check.
PRELIMINARY CONTROLS
· Carefully clean the flange and cones
· Spring cover sliding
· Shaft terminal locking
ENCODER CHECK (see SELF-DIAGNOSTICS)
· POS = outside display: 0-127 turning the shaft by hand
LED matrix: Clockwise, anticlockwise
TEST OF PROPER ENCODER FUNCTIONING
1. Cleaning the encoder
Remove the snap cover on the chuck side.
Insert a tool until it touches the phase disc (use a soft brush to prevent damaging the decals).
Slowly turn the wheel by hand several times to allow the tool to remove any residual dust.
Never force the tool on the phase generator.
After cleaning, close the snap cover.
2. Positioning the encoder card
It is recommended to position the encoder card in the following cases:
- If replacing the encoder card;
- If replacing, cleaning or generally working on the encoder decals;
- In the event of repeated errors 1,2,11,12,13,14,15,16,17,18 detected by the wheel balancer during the unbalance
measurement phase;
- In the event of unjustified unbalance oscillation.
Before running the encoder test, ALWAYS check that there is a maximum distance of 1 mm between the decal and
the encoder card and that the retaining nuts of the encoder card are adequately tightened.
Use a wheel of average dimensions.
Press:
[MENU]
[ ] The word [Setup] appears
[ENTER] The word [Diagn.] appears
[MENU]+[STOP]+[MENU] Press in sequence in maximum 5 sec.
[ ] The word [Enc.] appears
[ENTER] The word [Start] appears
[START] The test cycle is run after which the following results must be obtained for
the encoder to function properly:
[ 32] [ 32] Number of encoder pulses A/B
[Min.] [0.15] The number displayed must be in a range of 0.12%0.25.
[xxx] [xxx] The number shown on the left-hand display must be higher by as much
as possible than the right-hand number and both values must be as far
as possible away from 0.
MEANING OF ENCODER TEST ERRORS
Err. 1 No reset signal. 1. Check the connection cable between the encoder card and
the CPU board.
2. Check positioning of the encoder card.
3. Clean the encoder decal.
4. Replace the encoder card
5. Replace the CPU board
Err. 2 Encoder test speed not reached. 1. Check positioning of the encoder card.
2. Clean the encoder decal.
3. Replace the encoder card
4. Replace the CPU board
Err. 4 Incorrect direction of rotation. 1. Check the encoder card connection cable.
Err. 33 Rising edge fault detected for ENCA. 1. Check positioning of the encoder card.
2. Clean the encoder decal.

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Err. 34 Falling edge fault detected for
ENCB.
1. Check positioning of the encoder card.
2. Clean the encoder decal.
Err. 35 Falling edge fault detected for
ENCA.
1. Check positioning of the encoder card.
2. Clean the encoder decal.
Err. 36 Rising edge fault detected for ENCB. 1. Check positioning of the encoder card.
2. Clean the encoder decal.
Err. 37 Detected irregular behaviour of the
ENCA falling edge with respect to
the reset rising edge.
1. Check positioning of the encoder card.
2. Clean the encoder decal.
3. Move the encoder card up or down.
Err. 38 Detected irregular behaviour of the
ENCB falling edge with respect to
the reset rising edge.
1. Check positioning of the encoder card.
2. Clean the encoder decal.
3. Move the encoder card up or down.
STOP [STOP] button pressed during test. 1. Repeat the test.
3. Encoder count test
Press:
[MENU]
[ ]
[ENTER] The word [dIAgn.] appears
[ENTER] Confirm
After a brief LED and display test, the wheel position appears on the right-hand display, which must vary in the range
0%127 in a full turn.
On the LED matrix ↑ must appear in clockwise direction and ↓ in anticlockwise direction.
WHEEL BALANCING MACHINE CALIBRATION (see SELF CALIBRATION)
· Use a wheel with steel rim of average dimensions e.g. : 6” x 14” (± 1”)
· Set precise measurements (input by hand if necessary)
· Perform self-calibration
CHECKING MACHINE OSCILLATION
After running autocalibration, press [STOP] to return to the standard measuring frame.
Without locking the wheel, measure the machine oscillation as follows:
[MENU]
[ ]
[ENTER]
[MENU]+[STOP]+[MENU] Press in sequence in maximum 5 sec.
The words [Lan] [ci] appear
[ENTER] Confirm.
The letters [t.L.] [ 10] appear
[START] A cycle of 10 spins is run with automatic calculation and display
of the maximum oscillation (max. permitted +/- 2 g).
[ENTER] The following appears [Ini] [~120]: indicates the average unbalance measure
ment start speed in rpm.
[ENTER] The following appears [End] [~100]: indicates the average unbalance measure
ment end speed in rpm.
N.B.: The difference between the unbalance measurement start and end speed must never be more than 30 rpm.
[ENTER] End of test.
[STOP] Return to the standard measuring frame
If you wish to run more than 10 automatic spins, when [t.L.] [10] appears press the buttons [+]/[-] to select the desired
number in the range 5%999.
CHECKING MACHINE CALIBRATION
With the wheel perfectly balanced, apply 100 g first on the outside and then on the inside.
The wheel balancer must measure:
FI=0 FE=100 Weight F.E. = position = 6 o’clock
FI=100 FE=0 Weight F.I. = position = 6 o’clock
Max. permitted tolerance 100 g = 5%.
CHECKING THE FLANGE
When the wheel is perfectly balanced, tip over by 180° and measure the unbalanced values.
MAX ERR =
Above all for this check, it is advisable to use a sample wheel with known max. unbalanced errors caused by
centering which, for metal wheels, are less than 10 gr.

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d I
d E
d E
d I
d I
d E
d I
d E
d I d E
b
b
a
a
a
b
b
b
I E
abh
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8 - 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 establish how to measure the rims and how the wheel 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-passing planes for the centres of gravity of the corrective weights.
Consider a typical rim: the size “l” in terms of width indicated by the rim manufacturer differs from the distance
measurement between the correction planes for rim thickness and physical dimensions of the counterweight, whose
centre of gravity is located at distance “h” from the rest point of the edge of the rim. The wheel 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 an insignificant
difference means that accurate calibration can be obtained regardless of whether the inner rim with “l” or outer width
“b” is preset. It is a good rule to add 1/4 inch to the value given by the manufacturer. As regards the ALU functions,
the machine performs the following approximations in addition to systematic correction of the centre of gravity of the
counterweight as seen above.
ALU 1
a = a preset + ¾”
b = b preset -1 ½”
dl = dE = d preset - 1”
ALU 2
a = a preset
b = b preset - ¾”
dl = d preset
dE = d preset - 1”
NOTE : I = INSIDE
E = OUTER SIDE
ALU 3
a = a preset - 8 mm
b = b preset - a
dl = d preset
dE = dI - 1”
ALU 4
a = a preset
b = b preset - a - 5 mm
dl = d preset
dE = dI - 2”
ALU 5 PAX
a = a preset - 8 mm
b = b preset - a
dl = d preset
dE = dI - 1”

Model1450
WheelBalancer

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Special maitenance M
INDEX page
1 - TO CHANGE SUPPLY VOLTAGE .................................................................................................................................3
2 - CHECKING OF THE RIM DISTANCE GAUGE .............................................................................................................3
3 - CALIBRATION OF AUTOMATIC GAUGES ..................................................................................................................4
3.1 - TO ENABLE THE GAUGES ..............................................................................................................................4
3.2 - CALIBRATION OF THE DISTANCE POTENTIOMETER ..................................................................................5
3.3 - CALIBRATION OF THE DIAMETER POTENTIOMETER .................................................................................5
4 - ASSEMBLY OF THE PIEZO MEASURERS ..................................................................................................................6
5 - LOGIC TROUBLE SHOOTING SEQUENCE ................................................................................................................7
6 - POWER LAYOUT DIAGRAM .......................................................................................................................................9
7 - TO REPLACE THE POWER BOARD .........................................................................................................................10
8 - HOW TO CHECK FUNCTIONING AND ACCURACY .................................................................................................11
9 - WHEEL MEASUREMENT AND SETTING ON THE WHEEL BALANCER ...............................................................14

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1 - TO CHANGE SUPPLY VOLTAGE
(See recommended spare parts lists and power layout diagram)
The balancing machine can run on 115 V - 50/60 Hz o 230V - 50/60Hz.
To change the supply voltage, proceed as follows:
1) Replace the motor,
2) Replace the entire power board or else modify the board as follows:
A) Replace the capacitor.
B) Replace the two transformers.
2 - CHECKING OF THE RIM DISTANCE GAUGE
Check that the ruler used for measuring the DISTANCE of the wheels reads 200 mm as measurement of
the distance from the adapter plane. If the graduated scale is changed, position it with the line indicating
20 at the fixed limit (reading point) when the gauge tip coincides with the adapter plane.
Reading point : 200 mm Adapter plane

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3 - CALIBRATION OF AUTOMATIC GAUGES
3.1 - TO ENABLE THE GAUGES
In the event of faulty operation or replacing a P.C.: board, proceed to set the gauges as follows:
- press in sequence and within 5 seconds from when has
been pressed.
- Always select ON using buttons
- confirm the selection
- cancels enabling in any phase.

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3.2 - CALIBRATION OF THE DISTANCE POTENTIOMETER
- Remove the weight shelf and refit the tip on the gauge rod.
- Back-off the screws fastening the pulley on the potentiometer shaft.
- Select on the FUNCTIONS MENU (CONTROL OF THE FUNCTIONS MENU) → SET UP → AUTODIAGNOSTIC
(SELF-DIAGNOSTICS)
- Scroll until the wording (diS) appears on the left display while a number appears on the right display,
which varies when the distance gauge is moved and represents a reference for calibrating the potentio-
meter.
- With the gauge fully retracted, turn the potentiometer shaft keeping the pulley still until a number
between 50 and 100 is read.
- Decrease by two numbers, then retighten the screws to secure the pulley on the shaft.
Carry out the DISTANCE GAUGE SET UP (RIM DISTANCE GAUGE).
3.3 - CALIBRATION OF THE DIAMETER POTENTIOMETER
- After CALIBRATION OF THE DISTANCE POTENTIOMETER press .
- The wording [dIA] appears on the left display, a number appears on the right display, which varies when
the gauge is turned and represents a reference for calibrating the potentiometer.
- Remove the diameter gauge from the gauge rod after backing off relative screw.
- Slightly pull out the gauge rod and rest its stop on the machine shaft in external position near the base.
- Turn the potentiometer shaft until a number between 50 and 100 is read, then place it back in its correct
work position.
- Lock the potentiometer with relative set screw
- Carry out the DIAMETER GAUGE SET UP (DIAMETER GAUGE).