Manitowoc Published 05-03-17, Control # 228-03 1-23
16000 SERVICE/MAINTENANCE MANUAL INTRODUCTION
SWING SYSTEM OPERATION
See Figure 1-13 and Figure 1-14.
One hydraulic swing pump drives two separate swing
motors. The hydraulic motors drive gearboxes that mesh
with the ring gear and turn the rotating bed to swing. The
swing system is controlled with the swing control handle
movement and node controllers. The swing control handle is
inoperable when the swing brake is applied. The rotating bed
is free to coast if the swing control handle is in the neutral
position.
The swing motors are controlled directly by the output fluid
volume of the swing pump. The node controllers do not
control the fixed displacement swing motors. Swing pressure
senders monitor the pressure on swing left and swing right
sides of closed loop system. An orifice across the swing
motor ports A and B allows smoother fluid flow when shifting
swing directions. Continuous changing of closed-loop fluid
occurs through leakage in the pumps and motors.
Swing speed is monitored by a sensor at one hydraulic
motor. Swing speed and swing torque can be selected for the
type of work being performed on the Function Mode screen
in Section 3.
When the swing control handle is moved from off, an input
signal is sent to the Node-1 controller. The Node-3 and 5
controllers send a 24 volt signal to enable the rear and right
side swing/travel alarms. When the swing control handle is
moved to off, an input signal is sent to the Node-1 controller.
The Node-3 and 5 controllers send a zero volt output signal
to disable the rear and right side swing/travel alarms.
Swing Brake
The swing system has a spring-applied hydraulically
released brake on the drive shafts.
The source hydraulic pressure for releasing the swing brake
is from the accessory/MAX-ER pump at 28 to 35 bar (406 to
508 psi). For swing brake operation, the system pressure
must be above 14 bar (203 psi) for full release of the brake. If
the system pressure is below 14 bar (203 psi), the swing
brake could be partially applied and damage the swing
system. If the brake pressure or electrical power is lost when
operating, the swing brake is applied.
After startup, place the swing brake switch in the off-park
position. An input voltage is sent to the Node-1 controller.
The Node-5 controller sends a 24 volt output to enable the
swing brake solenoid HS-1.
The swing brake valve shifts to hydraulically release the
swing brake from the shaft. Fluid from the piston end of the
cylinder flows to the tank.
Before shutdown, place the swing brake switch in the on-
park position. An input voltage is sent to the Node-1
controller. The Node-5 controller sends a zero-output voltage
to disable the swing brake solenoid HS-1.
The swing brake valve shifts to block fluid to the brake and
the swing brake is applied. Fluid from the brake flows to the
tank. Fluid the from rod end of cylinder flows to the tank.
Swing Right or Left
See Figure 1-13 and Figure 1-14.
When the swing control handle is moved to the left, an input
voltage of 2.4 volts or less is sent to the Node-1 controller.
The Node-3 controller sends a variable 0 to 24 volt output
that is divided by a resistor and applied to the swing pump
EDC. The pump EDC tilts the swashplate relative to the
handle movement. Fluid flows from the pump ports to the
motor ports, moving the rotating bed to the left.
When the swing control handle is moved to the right, an
input voltage of 2.6 volts or more is sent to the Node-1
controller. The Node-3 controller sends a variable 0 to 24 volt
output that is divided by a resistor and applied to the swing
pump EDC. The pump EDC tilts the swashplate relative to
the control handle movement. Fluid flows from the pump
ports to the motor ports, moving the rotating bed to the right.
As the swing control handle is moved to the neutral position,
The Node-1 controller compensates for the hydraulic system
leakage or changing engine speed. The Node-3 controller
sends a zero output voltage to adjust the pump swashplate
to the centered position.
When in a swinging motion, the preferred way to stop or slow
the crane is to move the swing control handle beyond center
in the opposite direction. This allows the rotating bed to
gradually stop.
To Next Page
Loading...
Need help?
General
