GLASS-CAB 9R5508 - Caterpillar

Illustration 1 g06218373
Medium Pressure
(1) Oil cooler
(2) Motor for rotation
(3) Line relief valves
(4) Auxiliary control valve
(5) Medium circuit relief valve
(6) Extend solenoid valve "A3"
(7) Retract solenoid valve "A3"
(8) Main control valve
(9) Solenoid valve for hydraulic lock
(10) Pump 1
(11) Pump 2
(12) Auxiliary pump
(13) Hydraulic tankMedium pressure is designed to provide oil to the work tool for tool rotation. An attachment valve is used to control the oil flow. This valve is shifted with proportional reducing valves that allow the operator complete electronic control over the tool rotation. An auxiliary pump is used to supply oil flow for medium pressure. A typical example of a work tool that will use medium pressure is a shear or a grapple.Reference: Refer to Testing and Adjusting, "Work Tool Parameter - Program" for the tool control system to change the settings for work tool operation.Reference: Refer to Testing and Adjusting, "Medium Pressure: Default Value of Work Tool Parameters" for the Tool Control System to reference the factory settings.
Table 1
Operation Lever List
Control Extension Retraction
Left Joystick Thumb Wheel Push Forward Push Backward
Electric Foot Pedal Push Forward Push Backward Attachment Valve Extended
Illustration 2 g06218380
Attachment valve extended
(2) Motor for rotation
(3) Line relief valves
(4) Auxiliary control valve
(5) Medium circuit relief valve
(6) Extend solenoid valve "A3"
(10) Pump 1
(11) Pump 2
(12) Auxiliary pumpWhen the device for activation is operated in the extend position, proportional reducing valve (6) receives a modulated signal from the machine ECM. Proportional reducing valve (6) allows pilot oil to flow to attachment control valve (4). This shifts attachment control valve (4) allowing medium pressure oil from auxiliary pump (12) to hydraulic rotator motor (2).Oil returning from the rotator motor flows through attachment control valve (4), oil cooler and back to the hydraulic tank.The working pressure for rotation is limited by medium circuit relief valve (5).Attachment Valve Retracted
Illustration 3 g06218392
Attachment valve retracted
(2) Motor for rotation
(3) Line relief valves
(4) Auxiliary control valve
(5) Medium circuit relief valve
(7) Retract solenoid valve "A3"
(10) Pump 1
(11) Pump 2
(12) Auxiliary pumpWhen the device for activation is operated in the retract position, proportional reducing valve (7) receives a modulated signal from the machine ECM. Proportional reducing valve (7) allows pilot oil to flow to attachment control valve (4). This shifts attachment control valve (4) allowing medium pressure oil from the auxiliary pump (12) to hydraulic rotator motor (2).Oil returning from the rotator motor flows through attachment control valve (4), oil cooler and back to the hydraulic tank.The working pressure for rotation is limited by medium circuit relief valve (5).