Bosch Rexroth DB 5X E Series Operating Instructions Manual page 48

48/56 Troubleshooting
Fault table
Bosch Rexroth AG, DB(W)...5X/...E, RE25802-B/09.19
The safety 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 23: Fault table
Fault Possible cause
The response A valve with unsuitable
pressure indicated response pressure has been
on the component installed.
marking is not
reached during
testing at the test
stand.
The response With type DB(W)..G...5X/...E:
pressure indicated The valve ports are mixed up.
on the component
marking is not
exceeded during
The safety valve is damaged and
testing at the test
blocked internally.
stand.
If the response A safety valve with insufficiently
pressure is exceeded, dimensioned flow was installed.
the system pressure
increases excessively
With type DB(W)..G...5X/...E:
even though
The valve ports are mixed up.
the safety valve
responds.
During bleeding,
the system pressure
The P port of the safety valve
exceeds the
is connected via a line with
10% limit above
excessive flow resistance.
the maximum
The T port of the safety valve
admissible pressure
is connected via a line with
(see EC Pressure
excessive flow resistance.
Equipment Directive
2014/68/EU,
Appendix I,
chap. 7.3).
The viscosity of the hydraulic
fluid is outside the valve
specification.
Safety valve response A safety valve with unsuitable
pressure is too low. response pressure has been
installed.
The difference between
operating pressure and
response pressure of the safety
valve is too small.
Remedy
Check the specified response pressure
of the valve by means of the last figure
of the component marking at the valve
or name plate.
Select and order a valve with suitable
response pressure.
Check the ports; connect the safety
valve correctly. Observe the connection
designations P (pressure port) and T
(port of the discharge line).
Replace the safety valve.
Select and order a safety valve with
suitable specified flow.
Check the ports; connect the safety
valve correctly. Observe the connection
designations P and/or A (pressure
port) and T and/or B (port of the
discharge line).
Use larger supply pipes
(increase supply cross-sections);
avoid a deflection of flow.
Use larger discharge pipes (increase
outlet diameters), avoid a deflection of
flow, observe the maximum admissible
counter pressure in the discharge
line, see chapter 9.3 "Operation with
counter pressure in the discharge line".
Check whether a suitable hydraulic
fluid can be used in the system and
exchange the hydraulic fluid.
Check the specified response pressure
of the safety valve by means of the last
figure of the component marking at the
safety valve or name plate. Select and
order a safety valve with suitable
response pressure.
Check whether the system can be
operated at lower operating pressure
or select and order a safety valve with
suitable response pressure.