Troubleshooting
Sealing failure of the driving device.
Loosening of the bolt.
(5)
(13)
(17)
(14)
(4)
(4)
(10)
(7)
(4)
(4)
Buzzing noise
Wear of the armature.
Decline in the power supply voltage.
Foreign matter is caught in the armature.
(11)
Foreign matter is caught in the seat.
(16)
AC voltage is applied to the DC pilot valve.
Insufficient supply pressure and pilot pressure
Excessive oil supply.
(12)
(2)
(3)
Pilot pressure is decreased.
(5)
Swelling of the valve seal and piston seal.
(6)
Possible causes
Incorrect voltage.
(7)
(1)
(4)
Countermeasures
(Refer to the next page)
Perform troubleshooting with higher possibility based on the failure phenomenon.
Failure phenomenon
Open coil wire.
Foreign matter is caught in the armature.
The pilot valve switches, but
the poppet valve does not, or
there is a delay in switching.
Incorrect wiring.
Operation failure
The pilot valve can not switch.
Fuse blown out, breakage of lead wire.
Incorrect contact at the contact and connection.
(15)
(5)
Foreign matter is caught in the poppet.
(9)
(6)
Coil burnout.
Voltage is too high. Or incorrect coil.
(7)
Directly exposed to water.
(8)
Increase of the pilot pressure.
Foreign matter is caught in the armature.
Air leaks from the pilot exhaust.
The supply pressure fluctuates.
The pilot pressure fluctuates.
Air is consumed by the equipment on the
secondary side.
Or, air leaks from the piping on the
secondary side.
The set pressure fluctuates
even though the equipment
on the secondary side has
not been operated.
Pressure cannot be
adjusted
The seal has swelled, and the supply
poppet valve does not switch.
Foreign matter is caught in the poppet
valve on the exhaust side.
When the power is supplied,
a loud buzzing sound is
continuously generated.
The pressure does not
increase even if the signal
pressure is increased.
Sealing failure
Wearing of the valve seal / the piston seal.
Air leaks from the poppet valve.
Air leakage at connected part.
The poppet valve is not completely switched.
- 10 -
No.VEX
∗∗∗∗
-OMA0019-C
