Manitowoc MLC100-1 Service And Maintenance Manual

Manitowoc Published 10-09-2020, Control # 259-06 6-3
MLC80A-1/MLC90A-1/MLC100A-1/MLC100-1 SERVICE/MAINTENANCE MANUAL SWING SYSTEM
6
Swing Left
When joystick J1 is moved to the left, the joystick sends a
swing left command to the CCS. The CCS then ramps up the
PWM duty cycle to the proportional solenoid A in the swing
pump EDC to move the pump swashplate to a position that
meets the direction and speed commanded by the joystick
position.
The swing pump sends hydraulic fluid out port A on the pump
to port A on the motor. Hydraulic fluid then flows from port B
on the motor to port B on the pump to complete the closed-
loop circuit.
The swing encoder and swing left psi pressure sensor
provide closed-loop feedback to the CCS.
Cross Port Orifice
The orifice across the A and B sides of the closed loop
provides smoother hydraulic fluid flow when shifting swing
directions.
Swing Right
When joystick J1 is moved to the right, the joystick sends a
swing right command to the CCS. The CCS then ramps up
the PWM duty cycle to the proportional solenoid B in the
swing pump EDC to move the pump swashplate to a position
that meets the direction and speed commanded by the
joystick position.
The swing pump sends hydraulic fluid out port B on the pump
to port B on the motor. Hydraulic fluid then flows from port A
on the motor to port A on the pump to complete the closed-
loop circuit.
The swing encoder and swing right psi pressure sensor
provide closed-loop feedback to the CCS.
Coasting
When joystick J1 is moved back to the neutral position, the
CCS ramps down the PWM signal to the energized A or B
solenoid in the swing pump EDC. This allows the springs to
center the spool inside the proportional solenoid valve,
causing the pump swashplate to de-stroke (move to the
center position) and stop hydraulic flow to the motor.
With joystick J1 in the neutral position and the swing brake
released, the crane is allowed to coast because of an orifice
located across the A and B sides of the closed loop. The
orifice is connected in parallel with ports A and B of the swing
motor, allowing a restricted amount of hydraulic fluid to flow
from one side of the motor to the other side without having to
go through the pump.
Swing Alarm
Whenever a PWM signal is sent to the swing pump EDC, the
CCS activates the swing alarm.
FOR REFERENCE
ONLY

Manitowoc MLC100-1 Specifications

General

Brand	Manitowoc
Model	MLC100-1
Category	Construction Equipment
Language	English