Manitowoc Published 05-09-17, Control # 014-28 1-21
16000 SERVICE/MAINTENANCE MANUAL INTRODUCTION
Pressure Senders and Speed Sensors
NOTE: The swing brake pressure sensor is only available
on cranes with the swing lock removed.
Pressure senders monitor drum system pressures, right/left
travel system pressure, swing right/left system pressure,
swing brake pressure (cranes that do not have a swing lock),
and accessory system pressure. Remote node controllers
receive 0 to 5 volt input signals for each system pressure
sender. Pressure senders transmit drum holding pressure
information to Node-1 controller.
Drum speed sensors detect speed in RPM and direction of
drum movement. Node-1 controller receives this information
as two out-of-phase square wave voltages that are
converted to counts. The controller compares control
handle voltage with pump output to determine when to vary
pump stroke.
System Faults
See Figure 1-12 for the following procedure.
Node-1 controller monitors and enables an alarm if any
system fault is detected and displays the fault on the crane
information screen (see Section 3).
When operating, all limit switches are closed, sending an
input voltage to Node-1 controller. If a limit switch is tripped,
the system node controller sends a zero output voltage to
that system pump EDC and brake solenoid. System pump
de-strokes and system brake valve shifts to apply brake.
Move control in the opposite direction away from limit to
correct the problem.
The limit bypass switch allows crane to be operated beyond
the limits for crane setup or maintenance only. For example,
to add wire rope on load drum or to remove wire rope from
load drum after an operating limit is enabled. The jib up limit
bypass switch allows the jib maximum up limit to be
bypassed when boom or luffing jib is lowered to ground.
Brake and Drum Pawl Operation
All load drums, boom/mast hoist, travel, and swing park
brakes are spring-applied and hydraulically released. Drums
3 (when configured with luffing jib), 4, and 5 have drum pawls
that are released with the selected park switch. When the
operator places the selected brake switch in off - park
position, the selected drum pawl is disengaged from drum.
Place selected brake switch in on - park position to apply
pawl to drum.
Node-1 controller releases the swing brake and swing lock
(past production) immediately when swing brake switch is
placed in off - park position.
The travel Node-controller releases brake with control
handle movement.
With a drum control handle command, Node-1 controller
does not release drum brake until pressure memory holding
pressure is reached to hold the load.
To Next Page
Loading...
Need help?
General
