Manitowoc MLC150-1, Руководство по техническому обслуживанию

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Manitowoc
Published 03-21-2021, Control # 264-01
3-13
MLC150-1 SERVICE/MAINTENANCE MANUAL ELECTRICAL SYSTEM
3
Limit Switches—Dual Contact
In the non-tripped state, a controller provides power to the
normally closed contact and grounds the normally open
contact. A controller digital input reads the applied power
through the normally closed contact back through the
common center terminal as a logic high. When the switch is
tripped, the normally closed contact opens, breaking the
current path through the common terminal. At the same time,
the normally open contact closes, grounding the common
terminal and sending a controller digital input a logic low
signal.
Dual contact limit switches are used to sense the travel limits
of the following crane functions:
• Drums 1 and 2 minimum bail limit
• Drums 4 pawl limit
• Counterweight up limit
• Boom up limit
• Luffing jib up limit
Limit Switches—Single Contact
In the non-tripped state, a controller provides power to the
normally closed contact. A controller digital input reads the
applied power back through the normally closed contact as a
logic high. When the switch is tripped, the normally closed
contact opens, breaking the current path through the
common terminal. The controller digital input reads this as a
logic low.
Single contact limit switches are used for the following crane
functions:
• Block-up limits: boom points and jib points
Solenoids
Solenoids are driven by controller digital outputs and activate
hydraulic valves and provide control of the following
cylinders, valves, and pumps:
Angle Sensors
A controller provides power to the angle sensor. The sensor
outputs an analog signal that is proportional to the sensor
angle. A controller analog input reads this output voltage,
and the controller software determines the mast angle based
upon the signal level. The angle sensors are used to
measure the following items:
• Gantry angle
• Boom angle
• Rotating bed pitch and roll
Alarms
A controller digital output drives the applicable alarm during
various operational states:
• Swing motion
• Travel motion
• Load approaching or exceeding capacity
Load Link Sensors
A controller digital output provides power to the load pin
sensors. A strain gauge within the load pin produces an
analog output current that is proportional to the load. A
controller analog input reads this output current, and the
controller software determines the value of the load based
upon the current level. The load pin sensors monitor the
following loads:
• Right and left links
Temperature Sensors
A controller digital output provides power to the temperature
sensor.
The sensor produces an analog output voltage that is
proportional to temperature. A controller analog input reads
this output voltage, and software determines the value of the
load based upon the current level.
Fuel Level Sensor
A controller digital output provides power to the fuel level
sensor. The sensor sends a signal through a resistor that is
proportional to the fuel level.
Hydraulic Fluid Level Switch
A controller digital output provides power to the hydraulic
fluid level sensor. The sensor sends a signal that is
proportional to the fluid level and sends this to a controller
analog input.
Pressure and Vacuum Switches
The pressure and vacuum switches are normally closed.
They open when the vacuum or pressure level exceeds the
setting of the switch. In the non-tripped state, a controller
digital output provides power to the normally closed contact.
A controller digital input reads the applied power through the
normally closed contact back through the center terminal as
a logic high. When the switch is tripped, the normally closed
contact opens, breaking the path of power through the center
terminal, and the controller reads this as a logic low.
Brake release cylinders System valves
Drum pawl cylinders Pin pusher cylinders
Gantry cylinders Cooler fan pump
REFERENCE
ONLY