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Pressure and flow control system SYDFE1 series 2X, 3X
| Troubleshooting
Bosch Rexroth AG, Edition 10.2021, RE 30011-B
Table 19: Malfunction table for SYDFE1 control systems
Malfunction
Possible cause
Remedy
Other unusual noise
Input speed too high
Machine or system manufacturer
Wrong direction of rotation
Machine or system manufacturer
Insufficient suction conditions, e.g. air in
the suction line, insufficient diameter of the
suction line, viscosity of the hydraulic fluid
too high, suction height too great, suction
pressure too low, foreign body in the suction
line
Check, whether shut-off valves are open
Machine or system manufacturer (e.g.
optimize inlet conditions, use suitable
hydraulic fluid)
Air-bleed control system completely, fill
suction line with hydraulic fluid
Remove foreign particles from the suction
line
Improper mounting of the control system
Check mounting of the control system
according to the instructions given by the
machine or system manufacturer. Observe
tightening torques
Improper mounting of attachment parts, e.g.
coupling and hydraulic lines
Mount attachments in accordance with
the instructions of the coupling or fitting
manufacturer
Air in the pump or in the pre-load valve
Bleed pump and pre-load valve
Wear/mechanical damage to the control
system
Replace control system, contact Rexroth
Service
No or insufficient pressure(<
4 bar)
Faulty mechanical drive (e.g. defective
coupling)
Machine or system manufacturer
Hydraulic fluid not within the optimum
viscosity range
Use suitable hydraulic fluid (machine or
system manufacturer)
Drive unit defective (e.g. hydraulic motor or
cylinder)
Machine or system manufacturer
Wear/mechanical damage
Replace control system, contact Rexroth
Service
Pressure fixed, ca. 5...12 bar,
cannot be changed
Supply voltage not within the permissible
range (21.6...33.6)
Diagnostics: Is the actual swivel angle value
(12c) 0 Volt? If yes, is the supply voltage
missing?
Check, whether all connectors are plugged
on the pilot valve
Check voltage at the control electronics
Command value for pressure, swivel angle or
power (optional) is 0 bar or 0 %, respectively
If you use, for example, exclusively closed-
loop pressure control, connect the swivel
angle command value (14c/16c) to +10 V...
U
B
The potentiometer for the (optional) power
limitation must not be at the left-hand limit
stop
Swivel angle sensor defective
Inspect swivel angle sensor, see 8.1.11
page 70
Spool jams in pilot valve
Contact Rexroth Service