Danfoss PVG 100 Service Manual page 22

Service Manual
PVG 100 Component Troubleshooting
Failure mode
Main spools are slow, driven by PVE 13 Bar [190
PSI] pilot system
Main spools will not move mechanically or
electrical
PVHC 25 bar [360 psi] pilot system - main spools
are slow
22
PVG 100 Proportional Valves
Cause
Contamination
Pump pressure too low - below 9 Bar [130 PSI]
High T0 pressure. Do not exceed 5 Bar [73 PSI]
tank pressure
Oil viscosity 460 mm2/S [2128 SUS] too high
(cold oil or incorrect viscosity oil)
T0 not being connected to tank or is restricted to
tank
Internal pressure reducing valve parts
misassembled
Contamination
Pump pressure too low - below 20 Bar [290 PSI]
High tank port pressure. Tank pressure should
not exceed 5 Bar [73 PSI]
Oil viscosity - 460 mm2/S [2128 SUS] too high
(cold oil or incorrect viscosity oil)
Serviceability: All internal components can be removed from the cavity, cleaned, inspected and
reassembled back into the valve
1. Use a 13 mm hex wrench to remove the plug, and then remove the spring. Spool and cone are not
removeable.
2. Clean all components with clean solvent
3. Correctly reassemble the components back into the cavity and torque the plug to 85 Nm [750
lbf•in].Pressure reducing pilot valve
11048807 • Rev BA • October 2014
Corrective action
Disassemble and clean
Closed center: System increase stand-by to 13
Bar [190 PSI]
Open center: Check gear per pump manufacture
procedure
Check system for other components before valve
inlet that may provide a path to tank
Clear restrictions in return system.
Warm up system or replace oil with correct
viscosity
Connect T0 (PVP) port option to tank or remove
restriction
Reassemble the internal pressure reducing valve
parts correctly
Disassemble and clean
Closed center: System increase stand-by to 20
Bar [290 PSI]
Open center: Check gear per pump
manufacturers procedure
Check system for other components before valve
inlet that may provide a path tank
Check for restrictions in return system and
remove
Warm up system or replace oil with correct
viscosity