Cylinder/Motor Responds Slowly To Remote Electrical Or Hydraulic Controller; Erratic Cylinder/Motor Response To Electrical Or Hydraulic Controller Operation; Hydraulic Oil Supply - Danfoss PVG 100 Service Manual

Service Manual
System Troubleshooting
Cause
Contamination in the hydraulic oil

Cylinder/Motor Responds Slowly to Remote Electrical or Hydraulic Controller

Cause
Insufficient system pressure
Main spool travel limited
Incorrect signal voltage from electrical controller
Incorrect hydraulic pressure signal from remote
hydraulic controller
Insufficient pilot oil - all sections
Insufficient LS pump stand by pressure
Flow is not load independent

Erratic Cylinder/Motor Response to Electrical or Hydraulic Controller Operation

Cause
Electrical actuator faulty
Main spool centering spring damaged
Main spool position feedback transducer signal
incorrect
Contamination in hydraulic oil
Air in hydraulic pilot lines
Hydraulic remote actuator faulty
Low hydraulic oil supply

Hydraulic Oil Supply

Cause
Pump not running
Insufficient oil in reservoir
18
PVG 100 Proportional Valves
Check
Take oil samples to confirm
Check
Install pressure gauge and record pressure
Check stops on manual lever controller end for
proper adjustment. Refer to
troubleshooting.
Check the signal voltage from the controller with
a volt meter
Check pressure from the remote hydraulic
controller - 25 Bar [360 PSI]
Check pilot for contamination and correctly
assembled parts - 10-15 bar [145-218 psi] Electric
- 25 bar [360 psi] Hydraulic
Check pilot PSI - 10-15 bar [145-218 psi] Electric -
25 bar [360 psi] Hydraulic
PVLP check for cracks
Check LS pressure vs load pressure
Check
Check signal from controller to PVE
Check tension rod for correct torque or damage
Check feedback pin for damage
Take oil sample
Check for air trapped in signal lines from the
controller to the valve section module
Check signal pressure from the remote hydraulic
controller
Check fluid level in reservoir
Check
Check prime mover for operation
Check condition of drive coupling
Check fluid level in reservoir
11048807 • Rev BA • October 2014
Corrective action
Flush hydraulic system. Fill with clean filtered oil.
Corrective action
If pressure is low adjust pressure setting to valve
specification or pump manufacturers
specification
Adjust the manual lever stops and torque the
Component jam nuts to 8 Nm [70 lbf•in] Do not exceed
maximum torque
If signal voltage is incorrect repair or replace
electrical controller
If pressure is too low, repair or replace remote
hydraulic controller per manufacturers
instructions.
Replace inlet module
Check with your Danfoss representative
Adjust or replace pump
Replace valve
Corrective action
Repair or replace PVE
Torque to 8 Nm [70 lbf•in] or replace
Replace PVE
Flush complete system.
Fill reservoir with clean filtered fluid per OEM
specification
Bleed air from the hose connection at the valve
section
Repair or replace cylinder/motor
Fill reservoir with clean filtered fluid per OEM
specification
Corrective action
Repair or replace prime mover
Repair or replace drive coupling
Fill with clean filtered oil