HENNESSY INDUSTRIES Coats IBS 2000, Service Manual And Troubleshooting Manual, Page: 5 / 40

Service Manual — COATS Model IBS 2000 • 1
Introduction
This service manual contains the functional checks,
troubleshooting, adjustment, and part replacement
instructions for COATS
®
Model IBS 2000 Wheel
Balancer. Exploded views, illustrations, and an indexed
parts list facilitate parts location, ordering, and replace-
ment. All adjustments and replacements can be ren-
dered with mechanic's or electrician's tools.
Safety Notes
HIGH VOLTAGES, HIGH TORQUE MOTORS, and
HIGH SPEED ROTATING WHEELS are present in
COATS wheel balancers. Follow the SAFETY RULES
when servicing any balancer:
1. DISCONNECT BALANCER from power source
before starting any parts replacement or internal adjust-
ment.
2. LOWER GUARD HOOD before starting cycle.
3. DO NOT WEAR LOOSE CLOTHING, such as neck-
ties, while servicing the balancer.
4. LONG HAIR should be worn UP, or under a HAT.
5. WHEELS MUST BE MOUNTED PROPERLY:
• Cones must be centered in the wheel before
tightening.
• The wheel must be forced up firmly against the
faceplate.
• The hub nut must be engaged by a minimum of
four (4) full threads.
• Tighten the hub nut rotating the wheel and strik-
ing a spoke of the hub nut with the heel of the
hand.
Caution! Failure to tighten the hub nut could
result in serious injury!
Principle Of Operation
The model IBS 2000 Wheel Balancer utilizes the prin-
ciple that any rigid body rotating about an axis through
the body can be balanced using weights mounted in
two planes. In this case the rigid body is an automobile
wheel and tire assembly which is mounted precisely on
center and rotated to measure the imbalance forces in
two planes. As the wheel rotates, any imbalance in the
wheel results in radial outward forces on the wheel and
the distances from the voltages produced by the piezo
sensors.
With the forces known at the planes of the piezos the
imbalance forces at the wheel planes can be calculated
by using the distance from the force transducer planes
to the wheel correction planes. These wheel imbalance
forces are displayed for the wheel planes selected dur-
ing the setup procedure so the correction weights can
be added. A check spin is recommended to assure that
the wheel is in fact balanced. For the measurement to
be accurate:
1) the wheel must be mounted precisely on center
2) the wheel plane parameters must be entered accu-
rately
3) the distance and diameter arm and the balancer
must be calibrated carefully.
The Model IBS 2000 Balancer uses several modules
to control the balancing sequence. The COATS
®
Direct
Drive system includes the following primary elements:
• Direct Drive Motor and Shaft Assembly
• Motor Controller Printed Circuit Board
• CPU Printed Circuit Board Assembly
• Touch Panel
• Display Printed Circuit Board
• LCD Display
The balancing operation is started by mounting the
wheel and then selecting the planes for the desired
placement of wheel weights from the touch panel. The
wheel parameters are then entered for distance, width,
and diameters appropriate for the correction planes
selected.
The measurement is started by pushing the START
switch or lowering the hood. The display PCB responds
to the START command by sending the command to
the CPU which begins the measurement cycle. The
CPU turns the SPIN SSR ON which powers the motor
in the forward direction. As soon as the motor reaches
the measurement speed the power is removed and the
wheel coasts while the signal from the piezos is being
measured. When the measurement is completed the
CPU turns on the BRAKE SSR which reverses the
motor and brings the wheel to a stop. The WEIGHT and
POSITION readings for each plane are sent from the
CPU to the Display PCB where they are displayed. The
correction planes can be changed if desired and the dis-
plays are updated automatically.
Direct Drive