Operating_Instructions_RPE3-062x/xS3_14087_1en_05/2022
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The user is only authorized to replace the seal on the valve base and the solenoid coil. These parts are supplied as spare parts.
6.6
Repairs carried out by specialist
6.6.1 Removing the valve and replacing the seal on the connection surface
› Make sure that the circuit is depressurized and the power supply to the electrical parts is turned off.
› If the device has been in operation, it is necessary to let the circuit cool down to avoid burns from parts of the circuit.
› Disconnect the coil connector socket and the position sensor connector socket. Make sure that the inner areas of the plugs with contacts in
particular are free from dirt and contamination with working fluid.
› Using a size 4 inbus wrench, loosen all four valve mounting screws one at a time and remove the valve from the connection plate. Allow for the
fact that the interior of the valve contains a residual amount of working fluid that will begin to leak out after removal. We recommend that you
immediately place the valve in a prepared suitable container, e.g. a smaller plastic box, to avoid contamination of the machine and the floor.
› For example, use a small screwdriver to remove the four sealing rings from the recesses at the base of the valve body. Clean the valve connection
surface and plate, check for damage to the surfaces and insert new, undamaged sealing rings. Remount the valve and connect the electrical
connectors (see chapter 6.2 Product installation).
› Verify proper operation of the valve, that it is sealed in the safe mode of operation. It is recommended to start the test at low circuit pressure.
6.7 Product maintenance
6.7.1 The valve does not require maintenance during normal operation. Continuous inspection is recommended at appropriate intervals depending
on the environment and operating conditions
:
› external leakage
› no damage to electrical wiring and connectors
› fixing the electrical connectors of the coil and sensor
› clogging of the filter cartridge and contamination of the working fluid
6.6.2 Replacing the solenoid coil
If the function of the solenoid coil is lost, or if it is necessary to change the coil type (connector type, control voltage), dismantle the coil and replace it
with a new one.
› Make sure that the circuit is depressurized and the power supply to the electrical parts is turned off.
› If the device has been in operation, it is necessary to let the circuit cool down to avoid burns from parts of the circuit.
› Disconnect the plug of the coil connector. Make sure that the inner area of the socket with the contacts in particular is not dirty and contaminated
with working fluid.
› Remove the plastic nut at the end of the control system.
› Remove the coil.
› Take a new coil and check that it is the correct type according to the description on the casing.
› Place the new coil on the control system, with the connector closer to the valve body.
› Rotate the coil through the connector to the desired position and secure the position of the coil by tightening the plastic nut to 3+1 Nm.
› Check the connector socket for cleanliness and damage and insert it into the connector on the coil.
› An inadequately fastened connector can cause unreliable operation of the solenoid, especially when subjected to vibration.
› Check the solenoid function in the safe operation mode of the device, for example when the circuit pressure is low.
Repairs to a defective valve are only carried out by the manufacturer. Remove residual working fluid from the disassembled defective valve and
package it to prevent mechanical damage and contamination outside the package during shipment. Send the packaged valve with a description
of the manifestation of the defect to the manufacturer. A new valve is warranted by the manufacturer for 1 year. However, a claim may not be
accepted by the manufacturer if the valve is mechanically damaged, the seal material is damaged by aggressive liquid, or the valve has been shown
to have been used improperly and not in accordance with these instructions.
6.7.2 Checking the function of the position sensor
In view of the use of the valve as a functional safety feature, it is necessary to check the function of the spool position sensor at appropriate
intervals, but no later than after two years. A function check must also be carried out before the machine or system is started up after repair or
maintenance, or when a malfunction of the sensor is suspected.
a) Checking the electrical function of the spool position sensor
Position of the pins of the position sensor connector:
Pin 1: Sensor power supply 24 V DC ± 20% / I
MAX
= 20 mA
Pin 2: transistor switched output 1
Pin 3: transistor switched inverted output 1
Pin 4: grounding
1
2
4
3
Spool position
Connection during measurement
Voltage values
Spool in basic position held by springs, coil
without electrical supply
Voltage of pin 4 against pin 3
Max. 1,8 V DC (logic zero)
Voltage of pin 2 against pin 3
Min. Ub – 2,5 V DC (logic one)
Spool switched by solenoid to working
position, coil energized
Voltage of pin 4 against pin 3
Min. Ub – 2,5 V DC (logic one)
Voltage of pin 2 against pin 3
Max. 1,8 V DC (logic zero)
Ub – supply voltage of the position sensor [V DC]
