86/96
SYDFED-2X, SYDFED-3X, SYHDFED-1X
| Troubleshooting
Bosch Rexroth AG, Edition 11.2021, RE 30017-B
Table 28: Fault table of SY(H)DFED control systems
Malfunction
Possible cause
Remedy
Hydraulic fluid temperature too
high
Inlet temperature at control system too high
Inspect system, e.g. for malfunction of the
cooler, insufficient hydraulic fluid in the
tank
DB in pre-load valve opens
Diagnosis: Pipe to the tank heats up
Pressure must be lower than the cracking
pressure of the pre-load valve. Keep
overshoots and pressure pulsation to a
minimum.
Malfunction of pressure control valves (e.g.
high pressure relief valve, pressure cut-off
valve, pressure controller)
Contact Rexroth Service
Control system worn out
Replace control system, contact Rexroth
Service
15.3.1 Swivel angle measurement check
The settings for swivel angle measurement are made in the factory. The settings
described below must only be made after a replacement of the swivel angle
transducer.
Depending on circumstances, a calibration of the swivel angle “100 %“ can be
conducted while the drive motor is running or at rest.
15.3.1.1 Checking swivel angle “zero“ (while system is running)
1.
Close all directional valves
2.
Apply a swivel angle command value of >50 %
3.
Apply a pressure command value of 20 bar
4.
Check, whether the actual swivel angle value (α
act
) is 0 V ±1 mV The resulting
actual pressure value must be ca. 20 bar.
5.
In case of deviations start the calibration of the swivel angle sensor zero point.
15.3.1.2 Checking swivel angle “100%“ (while system is running)
1.
Apply a pressure command value of 100 bar, activate pressure controller only in
changeover logic
2.
Direct the full flow via the actuator, e.g. activate hydraulic motor or set
pressure relief valve to ca. 20 bar; in this case, the pilot valve deliberately
signals a warning (excessive control deviation)
3.
Check, whether the actual swivel angle value (α
act
) is 100 % ±1 % In the case of
deviations start the calibration of the swivel angle sensor factor.
15.3.1.3 Checking swivel angle “100%“ (while drive motor is switched off)
1.
Switch the hydraulic system off and wait for ca. 5 min until the pump has
swiveled out mechanically (wait until pressure reduction is completed).
2.
Check, whether the actual swivel angle value (α
act
) is 100 % ±1 % In the case of
deviations, observe point 3.
