Table Of Contents - Danfoss 51 Series Service Manual

Service Manual
Contents
Introduction
Pressure measurements
Adjustments
PCOR
Multifunction block
A7, L1, L2, L7 Controls
D7, D8, DA, DC Controls
Series 51 Electrohydraulic Proportional Controls Service Manual
Safety Precautions............................................................................................................................................................................5
Unintended Machine Movement..........................................................................................................................................5
Flammable Cleaning Solvents................................................................................................................................................5
Fluid Under Pressure..................................................................................................................................................................5
Personal Safety.............................................................................................................................................................................5
Hazardous Material.....................................................................................................................................................................5
Symbols used in Danfoss literature............................................................................................................................................6
Overview..............................................................................................................................................................................................6
General Instructions........................................................................................................................................................................ 7
Keep it Clean................................................................................................................................................................................. 7
Inspect for System Contamination....................................................................................................................................... 7
Replace the O-rings and Gaskets...........................................................................................................................................7
Lubricate all Moving Parts........................................................................................................................................................7
Torque Procedure....................................................................................................................................................................... 7
General Description.........................................................................................................................................................................7
Overview........................................................................................................................................................................................ 7
Multifunction Block.................................................................................................................................................................... 7
Pressure Compensating OverRide (PCOR) Option..........................................................................................................8
Brake Pressure Defeat (BPD) option..................................................................................................................................... 8
Threshold and Ramp Springs............................................................................................................................................... 10
Port Locations and Gauge Installation................................................................................................................................... 11
Threshold Setting...........................................................................................................................................................................12
Checking Threshold Setting................................................................................................................................................. 12
Adjusting Threshold Setting.................................................................................................................................................12
Pressure compensator Override (PCOR) setting.................................................................................................................13
PCOR Adjustment.....................................................................................................................................................................13
Checking PCOR Setting on a Test Stand.......................................................................................................................... 14
Adjusting the PCOR Setting..................................................................................................................................................14
Optional PCOR Housing Repair.................................................................................................................................................15
Disassembly................................................................................................................................................................................15
Inspection....................................................................................................................................................................................15
Assembly......................................................................................................................................................................................15
Optional Multifunction Block Repair.......................................................................................................................................17
Disassembly................................................................................................................................................................................17
Inspection....................................................................................................................................................................................18
Assembly......................................................................................................................................................................................18
Operation .........................................................................................................................................................................................19
General Description................................................................................................................................................................. 19
Proportional Solenoid.............................................................................................................................................................19
Check Valve.................................................................................................................................................................................19
Schematic......................................................................................................................................................................................... 21
Repair..................................................................................................................................................................................................21
Removing Solenoid..................................................................................................................................................................21
Disassembly................................................................................................................................................................................21
Inspection....................................................................................................................................................................................23
Assembly......................................................................................................................................................................................23
Solenoid Assembly...................................................................................................................................................................23
Operation..........................................................................................................................................................................................24
General Description................................................................................................................................................................. 24
11009448 • Rev BA • July 2014 3