Jacobsen Eclipse 322, Руководство по ремонту

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4-64 4222983 Second Edition
ELECTRICAL
4
As the steering wheel is turned to the right, the SCU will
continue to move the steering motor to the right until the
steering wheel stops turning or when the steering fork
reaches the magnetic trip zone of the right steering
proximity switch.
When the steering fork reaches the right proximity switch
trip zone, the proximity switch opens and stops providing
a signal to the SCU, and the SCU stops steering to the
right and provides full tactile-feedback to the steering
wheel. The same occurs when turning to the left side.
The SCU will increase the steering wheel turn ratio by
approximately 75 percent when the mow switch is placed
in the on position.
As the steering wheel is turned, AC power is provided
from SCU AC motor output terminals J53-U, J53-V, and
J53-W to steering motor AC motor terminals J54-U,
J54-V, and J54-W. To control the speed of the steering
motor, the SCU varies the frequency of the AC voltage
applied to the AC motor terminals. To Control the
direction of the steering motor, the SCU changes phase
of the AC voltage applied to the AC motor terminals.
The SCU encoder 1 input terminal J65-5 connects to
steering motor encoder 1 output terminal J55-2. The
SCU encoder 2 input terminal J65-6 connects to steering
motor encoder 2 output terminal J55-3. The encoders
provide to the SCU the direction and movement data of
the steering motor.
The steering motor temperature sensor output terminal
J55-4 provides a signal to SCU steering motor
temperature sensor input terminal J65-16. If the motor
temperature rises above 356° F (180° C), the SCU
communicates this condition to the MCU. Now the MCU
instructs LCD to turn on the alarm, fault LED, and to
display fault code 4210. The controllers communicate
through the controller area network (CAN).