Komatsu PC200-8M0 Shop Manual page 162

SEN06120-00
Operation of relief valve
When cylinder reaches its stroke end, main
q
relief valve opens.
q Pump discharge (Q) is relieved to the tank.
(For details, see "System diagram" of "Struc-
ture of CLSS".)
q Since the pump discharge pressure (PP) and
LS pressure (PLS) do not flow neither to the
upstream nor downstream, they become
approximately the same and LS differential
pressure (dPLS) becomes 0 MPa {0 kg/cm
As LS differential pressure (dPLS) is lower
q
than the LS set pressure of LS valve, LS valve
operates to make the pump swash plate angle
maximum.
Mechanically, operation of PC valve has prior-
q
ity over that of LS valve.
q The pump is maintained at the minimum swash
plate angle due to PC valve cut-off function.
20
10-402
2
}.
402 Hydraulic system, Part 2
Functions and operation by valve
PC200, 200LC, 220, 220LC-8M0