Komatsu PC500LC-10R Shop Manual page 306

COMPONENT PARTS OF WORK EQUIPMENT SYSTEM 10 STRUCTURE AND FUNCTION
FUNCTION OF EPC VALVE OF 1ST-LINE ATTACHMENT PPC VALVE
Upon receiving signal current (i) from the pump controller, this
valve generates EPC output pressure in proportion to that sig-
nal current and outputs it to the control valve.
OPERATION OF EPC VALVE OF 1ST-LINE ATTACHMENT PPC VALVE
When signal current is zero (coil is de-energized)
AEP2 1 6 3 6
1.
When the signal current from the controller does not flow into coil (4), coil (4) is de-energized.
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