Argo-Hytos RPEX3-06, Operating Instructions Manual

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Subject to change_RPEX3-06_14054_1en_03/2022
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WARNING
Switching solenoids
Directional control valves with two solenoids, coils must not be switched at the same time.
There is a risk of damaging the valves.
WARNING
Coil cooling
Coil cooling takes into account the cooling surface of the hydraulic part of the valve.
Do not power separately disassembled coils. Excessive winding heat, insulation damage and short circuiting
between coils may occur. For the same reason, the surface of the coils must not be covered, exposed to direct
heat sources or sunlight. The valve must not be closed in a tight space without ensuring air circulation.
7.3 Commissioning
Before commissioning the hydraulic ciruit, check that the valve is correctly mounted on the connection plate and that electrical supply cables are
correctly connected. The valve is not to be adjusted. Test operation should be conducted without the pressence of an explosive atmosphere. After the
hydraulic circuit has been commissioned, check the valve for leaks. Simply verify the directional control valve function, repositioning the spool by alter-
nately switching the solenoids and monitoring the movement of the appliance or the amount of pressure in the appliance branches (ports A and B).
7.4 Normal operation
During normal operation , the directional control valve spool is adjusted by the solenoids. Normal operation of the system does not require any
manipulation of the valve.
DO NOT exceed the MAXIMUM PARAMETERS , shown in table 4.4.
OBSERVE THE OPERATIONAL RESTRICTIONS AND AVOID THE RISKS , referred to in paragraph 3.
USE PROTECTIVE EQUIPMENT
When working with hydraulic fluid, it is recommended to wear safety goggles, protective rubber gloves and sturdy shoes with non-slip soles.
7.5 Exceptional and emergency situations
In the event of a power failure to the solenoids or a coil failure, the centering spring will return the valve spool to its base position.
Based on the results of the risk analysis, the following potential faults have been identified:
› External valve leakage due to seal damage associated with a working fluid leak.
› Loss of valve function, resulting in loss of control of the appliance.
› Mechanical damage to the electrical part of the valve, including the cable
DANGER
Shutdown of electrical power, pressure source and circuit relief
In the event of an emergency, immediately shut off the electrical power supply to the control solenoids and the
pressure source (pump). Relieve all parts of the hydraulic circuit including the hydraulic accumulators by
connecting them to the tank. A malfunctioning valve may cause a dangerous operating situation due to loss of
control. A damaged electrical part can initiate an explosion.
DANGER
Prohibition of handling and repair in explosive atmospheres
A defective valve must not be repaired or dismantled when an explosive atmosphere is present.
There is a risk of initiating an explosion.
WARNING
Check pressure relief part of the circuit
Always ensure that the circuit is depressurised before intervening in the hydraulic circuit, for example before
removing a valve. Otherwise there is a risk of leakage of working fluid and contamination of persons.
WARNING
Surface temperature
Before starting disassembly, make sure that the surface of the valve and solenoid coils has cooled to a low
enough temperature to prevent skin burns.
Defective valves must be replaced/repaired.