Manitowoc 16000 User Manual

Reference Only
INTRODUCTION 16000 SERVICE/MAINTENANCE MANUAL
1-66
Published 05-03-17, Control # 228-03
Counterweight Lift Cylinder
See Figure 1-53 and Figure 1-54.
When a MAX-ER chart is selected, a load sensing pin in one
mast strap monitors mast loading. The pin sends a variable
0.8 to 8.0 input voltage to the Node-1 controller for
controlling counterweight lift cylinder position. Node-1
controller converts the load-sensing pin voltage signal to U.S
tons that is displayed on MAX-ER information screen.
Counterweight lift cylinder automatically lifts the wheeled
counterweight assembly off the ground and sets it back down
when required depending on load (governed by boom angle,
boom length, lifted load). When the wheeled counterweight
assembly is off the ground, the crane can swing and travel in
the normal manner to position the crane and load. When the
wheeled counterweight assembly is on the ground, the
wheels must be properly positioned before swinging or
traveling the crane.
The Node-1 controller monitors the MAX-ER’s electronic and
hydraulic systems to automatically extend and retract the
counterweight lift cylinder to raise and lower the wheeled
counterweight assembly in response to changes in the mast
load sensing pin tension (see MAX-ER Operator Manual).
Pressure senders are located at the counterweight lift
cylinder to measure system inlet and outlet pressures and
send the pressure information as input voltage to the Node-1
controller. The information screen in the operator cab
indicates the lift cylinder pressures in metric or inch.
The counterweight lift cylinder position sensor monitors the
lift cylinder shaft position and sends the information as input
voltage to the Node-1 controller. The information screen in
the operator cab indicates the lift cylinder extend position in
percent.
Counterweight Lift Cylinder Switch
The counterweight lift cylinder switch allows the lift cylinder
to be disconnected from the mast straps during assembly/
disassembly. Power is available to the hand-held wireless
remote control when the engine is running, the MAX-ER
function mode is selected, and the power button is pressed.
The counterweight lift cylinder has a counterbalance valve at
each cylinder port to provide smooth operation. The
counterbalance valves lock the cylinder in position and also
provide relief protection for the cylinder. The counterweight
lift cylinder three position spool valves are motor spooled
where both cylinder ports and the tank port of valve spool
section are connected in the center position.
The crane accessory system pressure sender monitors the
system pressure to the counterweight lift cylinder system.
The Node-1 controller also monitors the lift cylinder pressure
senders in both the extend and retract directions. The Node-
1 controller sends a pressure output to the information
screen in the operator cab.
A position sensor at the bottom of the lift cylinder monitors
and sends a 0.8 to 8.0 voltage signal to the Node-1
controller. The Node-1 controller sends a percent output to
the information screen in operator cab.
Extend Counterweight Lift Cylinder
When the counterweight lift cylinder switch is moved and
held in the extend position, an input signal from the wireless
transmitter is sent to a receiver on the crane. The receiver
sends the input signal to the Node-1 controller. Node-7
sends a 24 volt output to enable the counterweight lift
cylinder solenoids HS-70 and 71 and shifts the valve to the
extend position.
The Node-3 controller also sends a variable 0 to 24 voltage
to enable the proportional relief solenoid HS-68 to provide
approximately 310 bar (4,496 psi) pressure to the
counterweight lift cylinder system.
Hydraulic pressure from the accessory pump flows through
the pressure control pilot valve, the three bank manifold
valve, and enters the free-flow check valve section of the
counterbalance valve. Fluid pressure on the piston end of
the cylinder extends the cylinder to the desired length.
Hydraulic fluid from the rod end of the cylinder is blocked by
the free-flow check valve section of the counterbalance valve
and the flow restraining section of the relief valve preset for a
relief setting of 152 bar (2,205 psi). The rod end cylinder
pressure opens the restraining section of the counterbalance
valve, allowing fluid to exit the valve. Return hydraulic fluid
passes through the three bank manifold valve before
returning to the crane hydraulic tank through the return line.
WARNING
Collapsing Mast!
After the mast straps are pinned to the lift cylinder
spreader, do not manually retract the counterweight lift
cylinder. The mast can be pulled over backwards. The lift
cylinder automatically adjusts when the MAX-ER is
operating.
Tipping Hazard!
The counterweight lift switch can be used to extend the
mast lifting cylinder manually if load-sensing pin fails. Any
other use of this control is neither intended nor approved.

Manitowoc 16000 Specifications

General

Brand	Manitowoc
Model	16000
Category	Construction Equipment
Language	English