Komatsu PC200-8M0 Shop Manual page 247

403 Hydraulic system, Part 3
Attachment circuit selector valve
Function
When a breaker is installed, the return oil from
q
the breaker does not pass through the main
valve, but returns directly to the hydraulic tank.
When other attachments (crusher, etc.) are
q
installed, the attachment and the main valve
are interconnected.
Operation
1. When attachment other than breaker
is installed
q Spool (1) is pressed to the left by the force of
spring (2).
Ports (ATT) and (V) are interconnected and
q
ports (ATT) and (T) are shut off. Attachment is
thus interconnected to the control valve.
PC200, 200LC, 220, 220LC-8M0
2. When breaker is installed
Pilot pressure from the attachment circuit
q
selector solenoid valve contracts spring (2),
and spool (1) moves to the right to the stroke
end.
q Ports (ATT) and (V) are shut off and ports
(ATT) and (T) are interconnected.
q Pressurized oil returning from the breaker
returns directly to the hydraulic tank through
port (T) without passing through the control
valve.
SEN06121-00
49
10-403