Manitowoc MLC150-1, Руководство по техническому обслуживанию

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ELECTRICAL SYSTEM MLC150-1 SERVICE/MAINTENANCE MANUAL
3-12
Published 03-21-2021, Control # 264-01
Control Module Devices
The control modules communicate with output devices to
control crane movement and with input devices to read crane
status. The following sections detail the operation of these
devices.
Pressure Transducers
A controller provides power to a pressure transducer. The
pressure transducers produce an analog input signal to the
controller that is proportional to the hydraulic pressure at the
transducer connection. The controllers monitor hydraulic
pressures to use as feedback in control algorithms and to
provide status information to the operator. Pressure
transducers are used to monitor the following:
• Drum system pressure
• Swing system pressure
• Accessory system pressure
• Track pressure
• Cooler fan pressure
Motor Speed Sensors
See Figure 3-7 for the following.
A controller provides power to Hall-effect speed sensors
within the hydraulic motors that drive the drums, rotating
bed, and crawlers. A gear wheel within the motor has teeth
that move past the speed sensor as a motor shaft spins,
causing the sensor to produce two square-wave signals that
are offset with a 90° phase delay. These signals are read at
frequency inputs of the controller.
The frequency of the square waves is determined by the
number of teeth on the circumference of the gear wheel and
shaft speed. The rotational direction is determined by which
signal phase leads the other. Software uses the square-
wave frequency and phase information to calculate the
rotational speed and direction of the motor.
FIGURE 3-7
Item Description
A Clockwise Rotation Signals
B Counterclockwise Rotation Signals
A
B
A
B
REFERENCE
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