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CHAPTER 1 AC/DC POWER DISTRIBUTION
Effective
09/2005
AC / DC DISTRIBUTION
The balancer is supplied with a power transformer. It is critical to have the proper input voltage in order for the
balncer to operate correctly. The transformer is rated at 9VAC @ 1900 milliamps. 9VAC is supplied to the Power
Supply pcb. The 9VAC passed through a bridge rectifier converting it into 12VDC. The 12VDC then is passed
through a voltage regulator coverting it into 5VDC which is used to power the processor pcb, display pcb and the
encoder pcb.
The processor pcb, display pcb and encoder all have an LED which signals that the pcb is receiving 5VDC
power.
To check power cable:
•
Disconnect the power supply.
•
Using a VOM, check for an output voltage at the end of the power plug 9VAC +/- 1VAC.
The electronic brake is controlled by a 12VDC solenoid. While the balancer is spinning, the main processor pcb
is gathering information from the encoder and transducers. After the needed information is gathered the main
pcb sends a signal to the power supply pcb which sends 12VDC to the brake solenoid braking the balancer and
bringing the shaft to a stop. This 12VDC can be checked at either X23 on the power supply pcb or directly at the
brake solenoid. 12VDC is only present during the brake cycle of the balancer.
DC THEORY OF OPERATION
PROCESSOR BOARD
The operating voltage for the Main Processor is 5VDC. It receives this power from the Power Supply Board
at X1 pins 32 and 34. This 5 volts also passes through the Processor Board and supplies the Encoder PCB
and the Distance SAPE.
ENCODER BOARD
The encoder receives 5VDC from the Processor Board. This voltage can be measured at the Processor
Board at X3 pin 6. The encoder is built so that there are no adjustments. The encoder disk is built onto the
shaft and cannot be replaced without replacing the vibratory member. The encoder is fitted in the vibratory
tube and consists of a reflective slotted sleeve which is mounted on the main shaft and the optoelectronic
unit.
DISTANCE POTENTIOMETER
The distance potentiometer is a 5K pot. It is supplied 5VDC from the main processor. This input voltage can
be measured at the Processor Board X6 pin 3. The output voltage is dependent upon the deflection of the
guage from the home position.
TRANSDUCERS
The transducers are installed in a manner that it forms a virtual transducer on each end of the shaft. This
configuration gives the balancer greater accuracy along with minimal amount of erroneous readings. Both
measuring transducers are arranged in one plane. The tranducers produce a DC output. The DC voltage that
is generated is sent back to the processor.
DISPLAY BOARD
The Display Board receives 5VDC from the Power Supply Board. This 5 volts can be checked at the harness
of the display board X2 pin 6 or at the Power Supply Board X2 pin 6.
KEYPAD
The keypad allows operator input to the Main Processor Board. The output signal passes through the Power
Supply Board directly to the Main Processor.