5.
MAIN RELIEF PRESSURE CHANGE CIRCUIT ARM CYLINDER BUCKET CYLINDER BOOM CYLINDER SWING MOTOR ps1 T3 T4 ps2 T1 T2 TRAVEL MOTOR pa11 pa10 B5 DR1 pc1 pb9 A5 pb5 ARM1 B9 A9 TURNING JOINT pa5 PO ARM2 pc1 pb9 pa5 (34,2) P2 B B1 A4 B4 OPTION B8 A8 pa9 pb8 Auto power boost (34,1) A A1 DR7 pc7 BUCKET DR2 pa11 pa8 pb3 A3 B3 BOOM2 pc2 A7 B7 pc2 pb3 pb7 pa3 pa7 pc7 A2 B2 pb2 pa3 SWING BOOM1 B6 B1 DR3 pc6 pa2 pc6 TRAVEL-RH pb6 pa6 A6 A1 pa1 pb1 TRAVEL-LH STRAIGHT TRAVEL pr1 P3 RCV PEDAL P T TRAVEL PT PS P1 P2 PH PA PP PS SH pa6 pb6 pb1 pa1 (4) (1) (2) (3) SWING ARM BUCKET BOOM P T P T Dr#, dr# A1 A2 POWER MAX SOLENOID VALVE FRONT PUMP REAR PUMP PILOT PUMP Pk (T/Joint) PH (MCV) (4) (1) (2) (3) a b d e f g h j c d1 h1 PS PS PS (4) (1) (2) (3) A5 A1 A2 A3 PG (S/Motor) pb5 pa2 pb2 pa9 pb8 pa8 pa7 pb7 h2 P3 P2 P4 PP(MCV) HYDRAULIC TANK T(dr1) P1 LINE FILTER RELIEF VALVE 900L3HC06 When the power max switch on the left control lever is pushed ON, the power max solenoid valve is actuated, the discharged oil from the pilot pump flow into PH port of the main relief valve of main control valve ; Then the setting pressure of the main control valve is raises from 330 kgf/cm 2 (4690 psi ) to 360 kgf/cm 2 (5120 psi ) for increasing the digging power.
And even when press continuously, it is canceled after 8 seconds. When the auto power boost function is selected to enable on the cluster, the pressure of the main relief pressure is automatically increased to 360 kgf/cm 2 (5120 psi ) as working condition by the MCU. It is also operated maximum 8 seconds. 3-10