Manitowoc 16000 User Manual

Reference Only
INTRODUCTION 16000 SERVICE/MAINTENANCE MANUAL
1-54
Published 05-03-17, Control # 228-03
Mast Lowering to Transport Position
See Figure 1-45.
Use the RCL Screen to select the Liftcrane Mast Handling
Capacity Chart. The mast controls will not operate and the
mast operating limits remain off until the Liftcrane Mast
Handling Capacities Chart is selected.
Use the mast switch on the hand-held wireless remote to
raise the mast assist arms until the cylinders stall and stop.
When the boom/mast hoist control handle is moved back for
raising, 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 boom/mast hoist pump EDC in the raise direction.
The Node-1 controller compares the drum holding pressure
to value in the pressure memory. When the system pressure
is high enough, the Node-4 controller sends a 24 volt output
to the drum brake solenoid HS-10. The drum brake valve
shifts to block the drain port and opens the port to the low-
pressure side of the pump to release the brake.
The boom/mast hoist pump EDC strokes the pump in the
raise direction. The Node-4 controller sends a 24 volt output
to enable mast raising cylinders solenoid HS-51 in the retract
(mast lowering) direction. The valve shifts to block the tank
port and open the port to the low-pressure side of pump.
As the mast lowers to the transport position, the boom/mast
drum hauls in wire rope between the boom and the mast
sheaves.
From the accessory valve, the fluid pressure enters the free-
flow check valve sections on side B of the load equalizing
valve. From the equalizing valve, fluid enters the
counterbalance valves and the rod end of the mast cylinders,
retracting the cylinder rods.
Fluid flow from the piston end of the mast raising cylinders is
blocked by the free-flow check valve sections on side A of
the counterbalance valves and flows through the valve flow
restrain sections preset for a relief pressure of 240 bar
(3,481 psi). The counterbalance valves operate with a 5:1
pilot ratio of the relief valve pressure, permitting the valve to
open when the pressure in the piston end of the cylinders is
approximately 48 bar (696 psi).
Hydraulic fluid from side A sections of both counterbalance
valves combines, and the free-flow check valve section on
side A of load equalizing valve blocks the flow. The fluid then
passes through the valve flow restrain section that is preset
at 276 bar (4,003 psi). The load equalizing valve operates
with a 1.5:1 pilot ratio of the relief valve pressure, permitting
the valve to open when the hydraulic pressure on side A of
the load-equalizing valve is approximately 185 bar (2,683
psi). The restraining section on side B of the load equalizing
valve opens, controlling the flow of the fluid out of the
cylinders to ensure the cylinder operation is balanced.
When the mast cylinders are retracting, the Node-3
controller monitors the boom/mast hoist drum speed sensor.
The Node-1 controller maintains a speed that is proportional
to the accessory system the hydraulic pressure applied to
the mast raising cylinders.
The Node-3 controller output voltage to the pump EDC is
relative to the control handle movement. The system pump
varies the flow to keep the drum at the handle command
setting. As the control handle is moved back, an output
voltage increases the pump swashplate angle.
The Node-3 controller monitors the mast angle sensor when
the mast is moving. When the mast is near 0°, the Node-3
controller sends a zero output voltage to the pump EDC that
moves the swashplate to the center position. After the
control handle center switch opens, the Node-4 controller
also sends a zero output voltage to disable the drum brake
solenoid HS-10 to apply the brake before the pump de-
strokes.
The Node-4 controller sends a zero output voltage to shift the
spool of the mast raising cylinder HS-51 to the center
position. The Node-3 controller sends a zero volt output to
disable the accessory system proportional relief solenoid
HS-68.
NOTE: It may be necessary to use the mast cylinders
switch to lower the mast fully.
FIGURE 1-45
Pressure
Sender
Accessory
Pump
Mast Raising
Cylinders
HS-68
HS-51
HS-50
Pressure
Sender
Drum 4
Pump
Drum 4
Motors
HS-10
16-1038

Manitowoc 16000 Specifications

General

Brand	Manitowoc
Model	16000
Category	Construction Equipment
Language	English