Komatsu PC500LC-10R Shop Manual page 266

COMPONENT PARTS OF HYDRAULIC SYSTEM
When pilot pressure (PST) is supplied (travel circuits independent from each
other)
1.
When pilot pressure (PST) from the travel junction solenoid valve is supplied, travel junction spool (2) com-
presses spring (1) and moves to the right, and port (PTL) and port (PTR) are disconnected.
2.
Independent oil flows are supplied to R.H. and L.H. travel motors.
TRAVEL PPC SHUTTLE VALVE OF CONTROL VALVE
PPC
Abbreviation for Proportional Pressure Control
10-172
10 STRUCTURE AND FUNCTION
PC500LC-10R
AEP21626