Komatsu Galeo PC800-8 Shop Manual page 263

10 Structure, function and maintenance standard
Operation
Heavy-lift
switch
Boom RAISE
OFF Operated
ON Operated
a Heavy-lift solenoid valve
For details of the structure and function, see Solenoid valve.
a Main relief valve
For details of the structure and function, see L.H. 5-spool control valve.
PC800, 850-8
Lever operation
Arm IN or
bucket CURL
—
Neutral
Operated
Heavy-lift Main relief
solenoid valve set
valve pressure
31.4 MPa
De-energized
{320 kg/cm
34.3 MPa
Energized
{350 kg/cm
If the arm IN or bucket CURL are operated during
boom RAISE operations, this function is automati-
cally canceled, and the condition becomes the
same as when the switch is turned OFF.
SEN00386-03
Boom lifting
CO control
Actuated
2 }
Canceled
}
2
force
Normal
10% up
Normal
21