Danfoss Series 45, Руководство по обслуживанию

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System pressure not reaching PC setting
Item Description Action
Check PC control setting. System pressure will not rise above PC setting. Adjust PC to appropriate setting. Refer to the
Adjustments chapter.
Check external relief valve. External relief valve setting below PC setting
presents pressure compensation. Adjust external relief valve according to
manufacturer’s recommendations. External relief
valve must be set above PC setting to operate
properly.
Inspect PC control spring. Broken, damaged, or missing spring will cause
erratic operation. Replace the spring as required.
Inspect PC spool for wear. Wear of PC spool causes internal leakage in the
control. Replace the spool as required.
Inspect PC spool for proper orientation. Improper orientation results in poor operation. Correct orientation of spool.
Check PC control for contamination. Contamination may interfere with movement of
the PC spool. Clean PC control components, take appropriate
action to eliminate contamination.
High inlet vacuum
C
Caution
High inlet vacuum causes cavitation which can damage internal pump components.
Item Description Action
Check fluid temperature. Low temperature increases viscosity. High fluid
viscosity causes high inlet vacuum. Allow system to warm up before operating.
Inspect inlet screen. Blocked or restricted inlet screen causes high
inlet vacuum. Clean screen/remove blockage.
Check inlet piping. Too many fittings, bends, or long piping causes
high inlet vacuum. Eliminate fittings to make path more direct.
Hydraulic fluid viscosity above acceptable limits. High fluid viscosity causes high inlet vacuum. Select fluid with appropriate viscosity for
expected operating temperature. See
Hydraulic
Fluids and Lubricants Technical Information
Manual
, 520L0463.
Service Manual
Series 45 E Frame Open Circuit Pumps
Troubleshooting
© Danfoss | September 2016 AX00000024en-US0401 | 23