Troubleshooting 39/44
RE29583-XH-B/09.19, 4WS2EM10..5X/...XH...,
Bosch Rexroth AG
14 Troubleshooting
14.1 How to proceed for troubleshooting
▶
Always work systematically and purposefully, even when under time pressure.
In the worst case, random, thoughtless disassembly and changing settings might
result in the inability to identify the original cause of error.
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First, get an overview of the functions of the valve in conjunction with the overall
system.
▶
Try to find out whether the valve has worked properly in conjunction with the
overall system before the error occurred.
▶
Try to determine any changes to the overall system in which the valve is
integrated:
– Were there any changes to the application conditions or area of application of
the valve?
– Have changes (e.g. refitting) or repair work been carried out at the overall
system (machine/system, electrical systems, control) or at the valve? If so:
What were they?
– Was the valve and/or the machine used as intended?
– How did the fault become apparent?
▶
Try to get a clear idea of the cause of error. Ask the direct machine operator.
The valve is not sensitive to faults as long as the specified application conditions are
complied with, in particular the oil quality and the operating temperature.
Table 11: Fault table
Error
Possible cause(s)
Remedy
Valve does not react
to control
Electrical connection
interrupted,
no current continuity
• Cable break at connection
cable
Replace the connection cable
• Mating connector not
connected
Connect the mating connector
• Connector without contact
Mating connector not connected
•
Valve-internal cable break
Remove valve and have it repaired
No pilot oil pressure available
• No pressure at X and/or P
Ensure the pilot oil supply
• Filter blocked
Exchange filter element and check system
for contamination
• Orifice blocked
Remove valve and have it repaired
Zero flow too high
• Control edges worn
Remove valve and have it repaired
Bad dynamic
behavior
• Filter contaminated
Exchange filter element and check system
for contamination
• Orifice contaminated
Remove valve and have it repaired
Instable zero point
• Control spool friction due to
contamination
Remove valve and have it repaired
Fault table
