Manitowoc MLC300 Service And Maintenance Manual

Reference Only
Manitowoc Published 11-22-17, Control # 257-02 10-11
MLC300 SERVICE/MAINTENANCE MANUAL ACCESSORIES
10
Retract (Lower)
See Figure 10-9 and Figure 10-10 for the following.
When a lower command is initiated by the setup remote or by
the S31 switch, the command is sent to the CCM-10 control
module. The CCM-10 control module then communicates
the lower command to the IOLC32 and IOLC33 control
modules via CAN Bus C.
The following then occurs:
• The CCM-10 control module increases the PWM current
to pump 4 to increase system A (left valve assembly)
hydraulic flow.
• The IOLC33 control module sends 24 V
DC
to the side A
solenoid on isolation valve A. The solenoid energizes
because the CCM-10 control module provides a ground
for the solenoid. The energized solenoid shifts the valve
spool to a position that routes hydraulic fluid to the live
mast assist arms valve.
• The IOLC32 control module then sends 24 V
DC
to the
corresponding solenoid on the live mast assist arms
valve, energizing the solenoid. The valve shifts to route
hydraulic fluid to the rod end side of the load-equalizing
valve.
• At the load-equalizing valve, hydraulic fluid flows
through the rod end check valve to the rod end
counterbalance valves. At the same time, pilot pressure
opens the barrel end load-equalizing valve.
• At the counterbalance valves, hydraulic fluid flows
through the rod end check valves into the rod end of the
cylinders. At the same time, pilot pressure opens the
barrel end counterbalance valves. As hydraulic fluid fills
the rod end of the cylinders, the rods retract to lower the
arms. This action forces hydraulic fluid out the barrel
ends of the cylinders, through the open counterbalance
valves, through the open load-equalizing valve, and
back to tank via the live mast assist arms valve.

Manitowoc MLC300 Specifications

General

Brand	Manitowoc
Model	MLC300
Category	Construction Equipment
Language	English