Doosan 5001, Инструкция по эксплуатации

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SP001622
Page 13
Solenoid Valve Assembly
Check Points and Solutions for Problems
Checking of Pilot Pressure for Defects
Symptoms Causes How to Check Solutions
Malfunction
of solenoid
valve
Foreign sub-
stance, dirt and
dust in solenoid
valve. Disassemble the solenoid valve and check if
there is any contamination such as a foreign sub-
stance and sludge between the case and the
spool. Remove contami-
nant, wash, and
assemble compo-
nents.
Tube or retainer
of solenoid valve
damaged. Disassemble the solenoid valve and check if
there is any deformation (bending or reduction) in
the tube or the retainer. Replace solenoid
valve.
Coil broken,
short, or burned. Disassemble the solenoid valve and check the
coil resistance.
Spec: 26.7
Ω
@ 20°C
Disconnection:
∞
Short: Low or excessive resistance
Disassemble the solenoid valve and check the
outside of the coil to see if its casing is burned
and melted.
Replace coil.
Connector termi-
nal ground defect. Check if the cap housing (where coil lead is
attached) and the housing (across its length) are
grounded properly. Replace housing or
terminal.
Pilot pres-
sure fails to
generate;
Pilot pressure. Remove plug of the "P5" port, install a pressure
gauge, and check the pilot pressure discharged
from the pilot pump when operating the pilot cut-
off valve (C1). Refer to "Causes"
and "How to Check"
of the solenoid
valve above.
Pilot relief valve. Check if the relief valve installed in the pilot line
operates properly.
• Check if pressure is bypassing
because of the presence of foreign
substance.
Remove foreign
substance, reas-
semble, and replace
the relief valve.
Pilot pump. Check if the pilot pump works properly. Replace the pilot
pump.
Pilot filter. Check if the mesh screen of the pilot filter is con-
taminated by foreign substance. Wash, reassemble,
and replace the fil-
ter.
Poor Actua-
tor Perfor-
mance
Pilot system. Check any defect of the pilot system considering
findings from "Pilot pressure fails to generate;"
category. Repair defect (s)
accordingly.
Solenoid valve. Install a pressure gauge at each outlet port of the
solenoid valve (HO, TR2, PH, and SP ports) and
check the pressure value discharged from the
pilot pump when operating the solenoid valve. Refer to "Causes"
and "How to Check"
of the solenoid
valve above.
Main control
valve. Check if main control valve of each component
works properly. Repair according to
findings.
Other compo-
nents. Check if each component works properly. Repair according to
findings.
Port where pressure gauge set up Screw Size Remark
P1, P3, P4, P5, P6, TR2, PH, HO, SP PF1/4" O-ring BOSS
Operate the solenoid valve
(ON).