Komatsu ecot3 PC300LC-8 Shop Manual page 213

10 Structure, function and maintenance standard
Function
The EPC valve consists of the proportional
q
solenoid portion and the hydraulic valve por-
tion.
q When it receives signal current (i) from the
pump controller, it generates the EPC output
pressure in proportion to the size of the signal,
and outputs it to the control valve.
PC300, 350-8
Operation
1) When signal current is 0
(coil is de-energized)
q When there is no signal current flowing from
the controller to coil (14), coil (14) is deener-
gized.
Spool (11) is pushed to the right by spring (12).
q
q Port (P) closes and the pressurized oil from the
front pump does not flow to the control valve.
The pressurized oil from the control valve is
q
drained to the tank via port (C) and port (T).
SEN01995-01
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