Komatsu PC200-8M0, Shop Manual

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SEN06120-00
10-402
34
PC200, 200LC, 220, 220LC-8M0
402 Hydraulic system, Part 2
Functions and operation by valve
When oil flowing from two pumps are divided [pump merge-divider valve changeover signals (IS1)
and (IS2) are ON]
Operation
q Since drive signal (IS1) of the main spool is ON, main spool (1) is moved to the left by the output pres-
sure from the pump merge-divider EPC valve. As a result, port (E) is disconnected from port (F).
q The pressurized oil from the two pumps are sent to respective control valve groups.
Pressure P1: To bucket, left travel, boom
Pressure P2: To swing, right travel, arm
q When drive signal (IS2) of the EPC valve for LS spool (3) becomes ON, LS spool (3) is also moved to
the left by the output pressure from the pump merge-divider EPC valve. As a result, ports (A) and (C)
are interconnected, and other ports remain disconnected from each other.
q The LS pressures transmitted from respective control valve spools through LS circuits (5), (6), (7), and
(8) are transmitted to respective control valves.