Manitowoc 2250 Service Maintenance Manual

Reference Only
Manitowoc Published 07-19-16, Control # 249-01 1-95
2250 SERVICE/MAINTENANCE MANUAL INTRODUCTION
1
Drum 9 Brake
Drum 9 motors have hydraulic disc brakes that are spring-
applied and hydraulically released. The brakes start to
release at 13 bar (188 psi) and are fully released at 17 bar
(246 psi). The PC controls the drum 9 disc brake release
solenoid HS-56 with movement of the left control handle,
when the drum 9 brake switch is in the OFF position. Drum 9
pawl is released and applied with the drum 9 brake switch.
Drum 9 Hoisting (MAX-ER Mode)
See Figure 1-61 and Figure 1-62 for the following.
When the left control handle (drum 9) is moved back to
RAISE, the handle’s neutral switch closes, sending an output
voltage of 5 V or more to the crane’s PC. The PC sends an
output signal to shift the diversion solenoid valve HS-54 to
allow fluid flow from the crawler’s travel pumps through the
diverting valve to the drum 9 motors.
The crane’s PC also sends a negative output signal to stroke
each of the crawler travel pump’s EDC in the RAISE direction
and a positive output signal to each motor’s PCP. The
crane’s PC checks that the block-up limit switches are closed
with no other systems’ operating limits present.
The PC compares drum-holding pressure to the value stored
in pressure memory. When system pressure is high enough,
the PC sends a positive output signal to enable the brake
solenoid HS-56. The brake solenoid shifts to block the tank
port and opens the port to system charge pressure to release
the brake.
The crane’s PC sends a negative output voltage to each of
the pumps’ EDC that tilts the swashplate to stroke each
pump in the RAISE direction. Hydraulic fluid at system
pressure up to 407 bar (5,900 psi) flows from pump ports A
to port A of the motors. Fluid from the motor ports B returns
to the pump ports B.
Right Travel Pump
Left Travel Pump
Servo Line
To Travel
Motors
Brake Line
from
Fan Circuit
T
T
HS54
RM-18
A
B
A
B
HS56
Crane
Drum 9
(350 psi)
24 bar
Swivel
Suction
Manifold
Suction
Manifold
From Boom
Hoist Charge Pump
A
B
B
A
Boom
UP
DOWN
DOWN
UP
Flow
Flow
FIGURE 1-62
(350 psi)
24 bar

Manitowoc 2250 Specifications

General

Brand	Manitowoc
Model	2250
Category	Construction Equipment
Language	English