Service Manual
PVG 32
powersolutions.danfoss.com
Service Manual
PVG 32 Proportional Valve Group
Revision history Table of revisions
Date Changed Rev
February 2017 Updated with PVE Series 7 0301
May 2014 Converted to Danfoss layout – DITA CMS BA
Feb 2006 - Aug 2013 Various changes AB - BA
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Service Manual
PVG 32 Proportional Valve Group
Contents
Introduction
Overview..............................................................................................................................................................................................5
General instructions........................................................................................................................................................................ 5
Remove the unit.......................................................................................................................................................................... 5
Keep it clean..................................................................................................................................................................................5
Replace all O-rings and gaskets............................................................................................................................................. 5
Secure the unit.............................................................................................................................................................................5
Safety precautions............................................................................................................................................................................6
Unintended machine movement..........................................................................................................................................6
Flammable cleaning solvents.................................................................................................................................................6
Fluid under pressure..................................................................................................................................................................6
Personal safety............................................................................................................................................................................. 6
Hazardous material.................................................................................................................................................................... 6
Acronyms.............................................................................................................................................................................................6
Operation
PVG 32 group with open center PVP (PVB with flow control spool)..............................................................................8
PVG 32 group with closed center PVP (PVB with flow control spool)........................................................................... 8
PVG 32 sectional drawing..............................................................................................................................................................9
PVPC plug for external pilot oil supply.....................................................................................................................................9
Friction detent.................................................................................................................................................................................11
PVBS, main spools for flow control (standard).................................................................................................................... 12
PVBS, main spools for flow control (with linear characteristics)................................................................................... 12
PVBS, main spools for pressure control................................................................................................................................. 12
PVPX Electrical LS unloading valve..........................................................................................................................................13
System Troubleshooting
Overview........................................................................................................................................................................................... 14
Troubleshooting a PVG valve.................................................................................................................................................... 14
No cylinder/motor response in either direction when remote controller is actuated......................................... 15
Cylinder/motor responds in one direction only................................................................................................................. 16
Main valve spool moves without oil passing to cylinder/motor.................................................................................. 16
Cylinder/motor operates without remote controller being operated....................................................................... 17
Cylinder/motor responds slowly to remote electrical or hydraulic controller actuation.................................... 17
Erratic cylinder/motor response to electrical or hydraulic controller operation....................................................17
Hydraulic oil supply.......................................................................................................................................................................18
Electrical supply..............................................................................................................................................................................18
Hydraulic (remote) pilot control pressure.............................................................................................................................19
PVG 32 Component Troubleshooting
Pressure relief valve.......................................................................................................................................................................20
Pressure reducing pilot valve.................................................................................................................................................... 20
Pressure gauge connection........................................................................................................................................................21
Open center plug...........................................................................................................................................................................22
Closed center plug and orifice.................................................................................................................................................. 23
Pressure adjustment spool.........................................................................................................................................................24
LS connection..................................................................................................................................................................................25
LS signal.............................................................................................................................................................................................25
Shuttle valve.................................................................................................................................................................................... 26
LS pressure limiting valve........................................................................................................................................................... 27
LS A, B shuttle..................................................................................................................................................................................27
Main spool........................................................................................................................................................................................ 28
Shock and anti-cavitation valve PVLP.....................................................................................................................................29
Pressure compensator..................................................................................................................................................................30
Load drop check valve ................................................................................................................................................................ 31
Maximum oil flow adjustment screws for ports A and B.................................................................................................32
PVM module.....................................................................................................................................................................................33
PVS module......................................................................................................................................................................................34
PVPVM module............................................................................................................................................................................... 35
PVAS module...................................................................................................................................................................................36
PVPX LS unloading valve.............................................................................................................................................................37
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Service Manual
PVG 32 Proportional Valve Group
Contents
PVEM, PVEA, PVEH, PVES electrical actuators...................................................................................................................... 38
Troubleshooting Considerations..............................................................................................................................................38
PVEO ON/OFF electrical actuator.............................................................................................................................................39
PVPC plug for external pilot control........................................................................................................................................42
PVMR Friction Module..................................................................................................................................................................42
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Service Manual
PVG 32 Proportional Valve Group
Introduction
Overview
This manual includes information for servicing PVG 32 valves. It includes a description of the units and
their individual components, troubleshooting information, and minor repair procedures.
Performing minor repairs may require removal from the vehicle/machine. Thoroughly clean the unit
before beginning maintenance or repair activities. Since dirt and contamination are the greatest enemies
of any type of hydraulic equipment, follow cleanliness requirements strictly. This is especially important
when changing the system filter and when removing hoses or plumbing.
A worldwide network of Danfoss Global Service Partners is available for major repairs. Danfoss trains and
certifies Global Service Partners on a regular basis. You can locate your nearest Global Service Partner
using the distributor locator at www.Danfoss.com.
For specifications and operating parameters on PVG 32 valves, refer to PVG 32 Technical Information
Manual 520L0344.
Do not attempt to service PVG valves without build sheet specifications for reference.
General instructions
Follow these general procedures when repairing PVG 32 valves.
Remove the unit
Chock the wheels on the vehicle or lock the mechanism to inhibit movement. Prior to performing repairs,
remove the unit from the vehicle/machine. Be aware that hydraulic fluid may be under high pressure
and/or hot. Inspect the outside of the valve stack and fittings for damage. Cap hoses after removal to
prevent contamination.
Keep it clean
Cleanliness is a primary means of assuring satisfactory motor life, on either new or repaired units. Clean
the outside of the valve thoroughly before disassembly. Take care to avoid contamination of the port
connections on the valve stack. Clean parts using a clean solvent wash and air dry.
As with any precision equipment, keep all parts free of foreign materials and chemicals. Protect all
exposed sealing surfaces and open cavities from damage and foreign material. If left unattended, cover
the valve with a protective layer of plastic.
Replace all O-rings and gaskets
Danfoss recommends you replace all O-rings. Lightly lubricate all O-rings with clean petroleum jelly prior
to assembly.
Secure the unit
For repair, place the unit in a stable position with the shaft pointing downward. Secure the motor while
removing and torquing controls, and valves.
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Service Manual
PVG 32 Proportional Valve Group
Introduction
Safety precautions
Always consider safety precautions before beginning a service procedure. Protect yourself and others
from injury. Take the following general precautions whenever servicing a hydraulic system.
Unintended machine movement
Warning
Unintended movement of the machine or mechanism may cause injury to the technician or bystanders.
To protect against unintended movement, secure the machine or disable/disconnect the mechanism
while servicing.
Flammable cleaning solvents
Warning
Some cleaning solvents are flammable. To avoid possible fire, do not use cleaning solvents in an area
where a source of ignition may be present.
Fluid under pressure
Acronyms
Warning
Escaping hydraulic fluid under pressure can have sufficient force to penetrate your skin causing serious
injury and/or infection. This fluid may also be hot enough to cause burns. Use caution when dealing with
hydraulic fluid under pressure. Relieve pressure in the system before removing hoses, fittings, gauges, or
components. Never use your hand or any other body part to check for leaks in a pressurized line. Seek
medical attention immediately if you are cut by hydraulic fluid.
Personal safety
Warning
Protect yourself from injury. Use proper safety equipment, including safety glasses, at all times.
Hazardous material
Warning
Hydraulic fluid contains hazardous material. Avoid prolonged contact with hydraulic fluid. Always
dispose of used hydraulic fluid according to state and federal environmental regulations.
This table provides a definition of commonly used terms.
P = Proportional V = Valve
PVP Pump side module
PVPV/M Pump side module
PVB Basic module
PVLA Anti-cavitation valve
PVLP Shock and anti-cavitation valve
PVS/PVSI End plate
PVAS (PVP, PVPV/M) Assembly kit for PVP, PVPV/M
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Service Manual
PVG 32 Proportional Valve Group
Introduction
PVPX, LS LS Unloading valve
PVPC Plug for external pilot oil supply
PVBS Main spool
PVM Mechanical activation
PVMD Cover for mechanical activation
PVH Cover for hydraulic activation
PVMF Cover for mechanical float
PVMR Cover for friction detent PVMR or float position
PVEH, PVES, PVEA Electrical activation
PVEM Electrical activation
PVEO Electrical activation
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Service Manual
PVG 32 Proportional Valve Group
Operation
PVG 32 group with open center PVP (PVB with flow control spool)
When the pump starts, and the main spools in the individual basic modules (11) are in the neutral
position, oil flows from the pump, through connection P, across the pressure adjustment spool (6) to
tank. The oil flow led across the pressure adjustment spool determines the pump pressure (stand-by
pressure).
When one or more of the main spools actuate, the highest load pressure is fed through the shuttle valve
circuit (10) to the spring chamber behind the pressure adjustment spool (6), and completely or partially
closes the connection to tank.
Pump applies pressure to the right-hand side of the pressure adjustment spool (6). The pressure relief
valve (1) opens if the load pressure exceeds the set value, diverting pump flow back to tank.
In a pressure-compensated basic module the compensator (14) maintains a constant
Pressure drop across the main spool—both when the load changes and when a module with a higher
load pressure is actuated.
With a non pressure-compensated basic module incorporating a load drop check valve (18) in channel P,
the check valve prevents return oil flow. The basic module can have the load drop check valve in channel
P for functions with over-center valves.
The shock valves PVLP (13) with fixed setting and the suction valves PVLA (17) on ports A and B are used
for the protection of the individual working function against overload and/or cavitation.
An adjustable Load Sensing (LS) pressure limiting valve (12) can be built into the A and B ports of
pressure-compensated basic modules to limit the pressure from the individual working functions.
The LS pressure limiting valves save energy compared to the shock valves PVLP. With PVLP all the oil flow
to the working function flows across the combined shock and suction valves to tank if the pressure
exceeds the fixed setting. With LS pressure limiting valves, an oil flow of about 2 l/min [0.5 US gal/min]
flows across the LS pressure limiting valve to tank if the pressure exceeds the valve setting.
PVG 32 group with closed center PVP (PVB with flow control spool)
In the closed center version, an orifice (5) and a plug (7) are fitted instead of the plug (4). This means that
the pressure adjustment spool (6) only opens to tank when the pressure in channel P exceeds the set
value of the pressure relief valve (1).
In LS systems, the load pressure flows to the pump regulator via the LS connection (8).
In the neutral position the pump control sets the displacement so that leakage in the system is
compensated to maintain the set stand-by pressure. When a main spool is actuated, the pump regulator
adjusts the displacement to maintain the set differential pressure between P and LS.
The pressure relief valve (1) in PVP should be set at a pressure of approximately 30 bar [435 psi] above
maximum system pressure (set on the pump or external pressure relief valve).
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1. Pressure relief valve
2. Pressure reduction valve for pilot oil supply
3. Pressure gauge connection
4. Plug, open centre
5. Orifice, closed centre
6. Pressure adjustment spool
7. Plug, closed centre
8. LS connection
9. LS signal
10. Shuttle valve
11. Main spool
12. LS pressure limiting valve
13. Shock and suction valve, PVLP
14. Pressure compensator
15. LS connection, port A
16. LS connection, port B
17. Suction valve, PVLA
18. Load drop check valve
19. Pilot oil supply for PVE
20. Max. oil flow adjustment screws for
ports A and B
PVP
PVB
PVB
Service Manual
PVG 32 Proportional Valve Group
Operation
PVG 32 sectional drawing
PVPC plug for external pilot oil supply
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PVPC with check valve for open center PVP
PVPC, with check valve, is used in systems where it is necessary to operate the PVG 32 valve by means of
the electrical remote control without pump flow. When the external solenoid valve is opened, oil from
Oil
Flow
Direction
Oil
Flow
Direction
Service Manual
PVG 32 Proportional Valve Group
Operation
the pressure side of the cylinder is fed via the PVPC through the pressure reducing valve to act as the
pilot supply for the electrical actuators.
This means that a load can be lowered by means of the remote control lever without starting the pump.
The built-in check valve prevents the oil from flowing via the pressure adjustment spool to tank.
With the pump functioning normally, the external solenoid valve is closed to ensure that the load is not
lowered due to the pilot supply oil flow requirement of approximately
1 l/min [0.26 US gal/min].
With closed center PVP, the external pilot oil supply can be connected to the pressure gauge connection
without the use of a PVPC plug.
PVPC without check valve for open center PVP
PVPC, without check valve, is used in systems where it is necessary to supply the PVG 32 valve with oil
from a manually operated emergency pump without directing oil flow to the pilot oil supply (oil
consumption about 1 l/min) [0.25 US gal/min].
When the main pump is working normally, the oil is directed through the PVPC plug through the
pressure reduction valve to the electrical actuators.
When the main pump flow fails, the external shuttle valve ensures that the oil flow from the manually
operated emergency pump is used to pilot open the over center valve and lower the load. The load can
only be lowered using the mechanical operating lever of the PVG 32 valve.
With closed center PVP, the external pilot oil supply can be connected to the pressure gauge connection
without the use of a PVPC plug.
For specifications on PVG 32 valves, refer to PVG 32 Technical Information Manual 520L0344.
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PVMF
P A F
(Standard assembly)
P
B F
(Optional assembly)
Service Manual
PVG 32 Proportional Valve Group
Operation
Friction detent
PVMR Friction detent
The friction detent PVMR allows the directional spool to be held in any position, resulting in infinitely
variable, pressure compensated flow. The spool position will be held indefinitely without the necessity of
holding the mechanical lever.
PVMR should only be used together with PVB basic modules with pressure compensator.
PVMF Mechanical float position lock
This allows the float spool to be held in the float position after release of the mechanical handle.
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PVMF
P B F
(Standard assembly)
P A F
(Optional assembly)
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Service Manual
PVG 32 Proportional Valve Group
Operation
PVBS, main spools for flow control (standard)
When using standard flow control spools, the pump pressure is determined by the highest load pressure.
This is done either via the pressure adjustment spool in open center PVP (fixed displacement pumps) or
via the pump regulator (variable displacement pumps).
In this way the pump pressure will always correspond to the load pressure plus the stand-by pressure of
the pressure adjustment spool or the pump regulator.
This will normally give optimum and stable adjustment of the oil flow.
PVBS, main spools for flow control (with linear characteristics)
PVBS main spools with linear characteristic have less dead band than standard spools and a completely
proportional ratio between control signal and oil flow in the range beyond the dead band.
Warning
PVBS with linear characteristic must never be used together with PVEM electrical actuators.
The interaction between the small dead band of the spools and the hysteresis of the PVEM actuator of
20% involves a risk of building up a LS pressure in neutral position.
PVBS, main spools for pressure control
In a few systems load sensing pump pressure may result in unstable adjustment of the oil flow and a
tendency towards system hunting. This may be the case with working functions that have a large
moment of inertia or over-center valves. In such systems main spools for pressure control can be
advantageous. The spools are designed in such a way that the pump pressure is controlled by the spool
travel. The main spool must be displaced until the pump pressure just exceeds the load pressure before
the working function is applied.
If the main spool is held in this position, the pump pressure will remain constant – even if the load
pressure changes – giving a stable system.
The use of pressure control spools, however, also means that:
the oil flow is load dependent
•
the dead band is load dependent
•
the pump pressure can exceed the load pressure by more than is usual.
•
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Service Manual
PVG 32 Proportional Valve Group
Operation
Due to these factors use pressure control spools only when you know for certain that problems with
stability will arise – or already have arisen.
Use LS
A/B
PVPX Electrical LS unloading valve
PVPX is a solenoid LS unloading valve. PVPX is fitted into the pump side module enabling a connection to
be made between the LS and the tank lines. Thus the LS signal can be relieved to tank by means of an
electric signal.
For a PVP pump side module in open center version the relief to tank of the LS signal means that the
pressure in the system is reduced to the sum of the tank port pressure plus the neutral flow pressure for
the pump side module.
For a PVP pump side module in closed center version, relief to tank of the LS signal occurs when the
pressure is reduced by the sum of the tank port pressure for the pump side module plus the stand-by
pressure of the pump.
when pressure stability is an issue.
Caution
Protect yourself from injury. Use proper safety equipment, including safety glasses, at all times.
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Service Manual
PVG 32 Proportional Valve Group
System Troubleshooting
Overview
Warning
This troubleshooting guide for the PVG valve assemblies does not cover valves that have been altered
from original valve build specifications
This section provides general steps to follow if undesirable system conditions are observed. Follow the
steps listed until the problem is solved. Some of the items will be system specific. Always observe the
safety precautions listed in the Introduction section, and related to your specific equipment.
Confirm that valve is built properly according to the specification sheet.
If necessary, install a lever to the valve to verify proper mechanical function.
Refer to PVG 32 Technical Information Manual 520L0344 for valve configuration information.
Refer to PVG 32 Parts Manual 11006794 for part numbers.
Troubleshooting a PVG valve
THINK - before troubleshooting a problem.
Every fault location process should follow a logical and systematic order.
It is wisest to start at the beginning:
Is the oil level correct when the pump is operating?
•
Is the condition of oil and filters acceptable?
•
Are pressure, flow, and flow direction as specified?
•
Is the oil temperature too high or too low (oil viscosity)?
•
Are there any unusual vibrations or noise (cavitation)?
•
If the driver of the vehicle is available, ask him:
What type of fault it is and how it affects the system?
•
How long he has he felt that something has been wrong?
•
If he has “fiddled” with the components?
•
If he has any hydraulic and electrical diagrams available?
•
Diagrams are often found in the instructions included with vehicles/machines.
Unfortunately they are often so technical that they are not of much use in a fault location situation.
However; the diagram usually shows the order of, and the connections between, the individual
components.
When a defective component is identified, clean the component and its surroundings before removal.
Remove loose paint from pipes and fittings.
Cover all holes, hoses and pipe ends with plugs or seal with, for example, plastic bags after removal to
avoid the entry of dirt during repairs.
Never disassemble hydraulic components outside.
Perform repairs in a workshop on a clean workbench (covered with clean cloth or newspaper).
Make sure that a Danfoss service manual for with the product is handy.
Follow the instructions word for word during disassembly and assembly.
If these instructions are not followed closely the system may not operate correctly after repairs are
completed.
Note that in some cases special tools are necessary for assembling the product.
Our service manuals give full guidance on use of special tools.
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Problem?
Mechanical
Mechanical
No
No
Hydraulic
Hydraulic
No
No
Electrical
Electrical
No
No
Electronic
Electronic
No
No
Software
Problem?Problem?
Mechanical
Mechanical
No
No
Mechanical
Mechanical
No
No
Hydraulic
Hydraulic
No
No
Hydraulic
Hydraulic
Hydraulic
Hydraulic
No
No
Electrical
Electrical
No
No
Electrical
Electrical
Electrical
Electrical
No
No
Electronic
Electronic
No
No
Electronic
Electronic
Electronic
Electronic
No
No
SoftwareSoftware
P107 823
Service Manual
PVG 32 Proportional Valve Group
System Troubleshooting
Troubleshooting flow chart
No cylinder/motor response in either direction when remote controller is actuated
Cause Check Corrective action
Verify if fault is mechanical, electrical
or hydraulic
Sticking main spool Remove manual, electrical, and hydraulic actuators
Internal filters blocked Check for blockage in internal filters Remove blockage
Operate manual lever to confirm mechanical or
electrical or hydraulic
from the valve section. Remove main spool from valve
section and inspected for damage. If no damage
reinstall the main valve spool and it should move
freely in the valve section bore.
Check movement of manual lever when electrical
controller is operated
Check movement of manual lever when hydraulic
controller is operated
If none of the above check pump per manufacturers
recommended procedure
If moving the manual lever operates the cylinder/motor
check electrical or hydraulic
Replace the valve module and main spool. If any damage
is found on the main spool
If manual lever does not move check electrical voltage
signal from controller, wiring at the PVE module
If manual lever does not move check hydraulic controller
pressure at the PVG valve module - 25 Bar [360 PSI]
Repair or replace pump per manufacturers
recommended procedure
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Service Manual
PVG 32 Proportional Valve Group
System Troubleshooting
Cylinder/motor responds in one direction only
Cause Check Corrective action
Verify if fault is mechanical, electrical
or hydraulic
Air in system Entrained air generates heat under pressure Look for foam or bubbles in reservoir. Check for leaks on
Internal leakage Excessive internal leakage may overheat the system. Install loop flushing defeat option and monitor case flow.
Shock valves Swap and see if problem follows Replace valves
Solenoid actuation If power is OK from controller Repair wiring to PVE module
Main spool travel restricted Stop on manual controller turned in too far Back out manual stop on manual controller
Remote electrical controller Insufficient signal from electrical controller Repair or replace electrical controller
PVEO connections Incorrect PVE/PVEO connections Connect correct way
Remote hydraulic controller PVRH Insufficient pilot oil pressure from remote hydraulic
Operate manual lever in both directions to confirm if
mechanical or electrical or hydraulic
If operating the manual lever strokes the cylinder/
motor in one direction only, check manual stop screw
adjustment
Check movement of manual lever when electrical
controller is operated
Check movement of manual lever when hydraulic
controller is operated
controller Pressure needs to be 25 Bar [360 psi]
If moving the manual lever operates the cylinder/motor
in both directions check electrical or hydraulic
Back out manual stop on manual controller and torque
the jam not to 8 Nm [70 lbf•in] Do not exceed maximum
torque
If manual lever does not move in one direction check
electrical signal from controller and wiring at the PVE
module
If manual lever does not move in both directions check
hydraulic pressure at the PVG module
inlet side of charge pump.
If case flow is excessive, motor may require major repair.
Contact Danfoss Service.
Repair or replace remote hydraulic controller
Main valve spool moves without oil passing to cylinder/motor
Cause Check Corrective action
Insufficient oil supply to valve Check the pump per manufacturers procedure Repair or replace pump per manufacturers procedure
Optional pressure compensator in
valve section not functioning
Insufficient load pressure at
compensator spring chamber
Cylinder/motor load too high for
pressure setting of the system
Blocked LS galleries Inspect for blockage in LS galleries Remove blockage in LS galleries
Shuttle valve faulty Inspect shuttle valve Repair or replace
Blocked LS lines to pump controller Inspect LS lines from PCG to pump controller Remove blockage in LS lines from the PVG valve to pump
Oil bypassing at shock valve/anticavitation check valve
Internal leakage in cylinder/motor Inspect for by-passing of oil per cylinder/motor
Too much leakage in LS spool in pump
control
Blocked thermal orifice check thermal orifice (blocked) Replace thermal orifice
Load too high for system Check for proper system pressure Adjust pressure to valve specification
Internal leakage in cylinder/motor Inspect for bypassing of oil per cylinder/motor
Shock valve or anti-cavitation check
valve faulty
System relief valve pressure set too low
for load
Check compensator spool Replace spool
LS drilling holes plugged Clean or replace
Check pressure at the valve If pressure is set to spec. per valve lower load on cylinder/
Check if stuck open or damaged Replace valve
manufacture per manufactures procedure
Check bleed orifice in LS control Use a LS pump control with no bleed orifice
manufacturer specification
Inspect for damage and contamination Repair or replace cylinder/motor
Install pressure gauge and check pressure
motor
controller
Repair or replace cylinder/motor per manufactures
procedure
Repair or replace cylinder/motor
Adjust pressure to system specification
Lower load
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PVG 32 Proportional Valve Group
System Troubleshooting
Cause Check Corrective action
Cylinder/motor load too high for
pressure settings of system
Cylinder/motor operates without remote controller being operated
Cause Check Corrective action
Spool control tension rod loose Confirm torque on spool control tension rod Torque to 8 Nm [70 lbf•in]
Electrical feedback transducer not in
neutral position
Remote electrical controller neutral
position switch faulty
Sticking pressure control valve in remote
hydraulic controller
Sticking main spool in valve section Remove manual, electrical, and hydraulic actuators from the
Internal fault in the PVE/PVEH/PVEM/
PVEO
Contamination in the hydraulic oil Take oil samples to confirm Flush hydraulic system. Fill with clean
Check load pressure at PVB-LS port Reduce load pressure if exceeds maximum pressure limit
Maximum system pressure should be approx. 25
Bar [365 PSI] above highest load pressure
Adjust pump pressure compensator setting if
necessary
Check the feedback pin in the PVE. It should be loose Replace transducer
Disconnect the connection at the PVE. It should come back to
neutral
Disconnect the hydraulic signal line from valve Repair or replace faulty remote hydraulic
valve section. Remove main spool from valve section and
inspected for damage. If no damage reinstall the main valve
spool. Spool should move freely in the valve section bore.
PVEO check continuity. All other PVE, check LED (Red means
internal error)
of the system
Adjust maximum system pressure if necessary
Repair or replace faulty switch or wiring at
remote controller
controller
Replace the valve module and main spool if
any damage is found on the main spool
Replace faulty PVE/PVEH/PVEM/PVEO
filtered oil.
Cylinder/motor responds slowly to remote electrical or hydraulic controller actuation
Cause Check Corrective action
Insufficient system pressure Install pressure gauge and record pressure If pressure is low adjust pressure setting to valve
Main spool travel limited
Incorrect signal voltage from
electrical controller
Incorrect hydraulic pressure signal
from remote hydraulic controller
Insufficient pilot oil - all sections Check pilot for contamination and correctly
Insufficient LS pump stand by
pressure
Flow is not load independent
Check stops on manual lever controller end for proper
adjustment.
Refer to Component troubleshooting section.
Check the signal voltage from the controller with a
volt meter
Check pressure from the remote hydraulic controller 25 Bar [360 PSI]
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
specification or pump manufacturers specification
Adjust the manual lever stops and torque the 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 NOTE: Check with S-D TST
Adjust or replace pump
Replace valve
Erratic cylinder/motor response to electrical or hydraulic controller operation
Cause Check Corrective action
Electrical actuator faulty Check signal from controller to PVE Repair or replace PVE
Main spool centering spring
damaged
Check tension rod for correct torque or damage Torque to 8 Nm [70 lbf•in] or replace
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PVG 32 Proportional Valve Group
System Troubleshooting
Cause Check Corrective action
Main spool position feedback
transducer signal incorrect
Contamination in hydraulic oil Take oil sample Flush complete system.
Air in hydraulic pilot lines Check for air trapped in signal lines from the
Hydraulic remote actuator faulty Check signal pressure from the remote hydraulic
Low hydraulic oil supply Check fluid level in reservoir Fill reservoir with clean filtered fluid per OEM
Hydraulic oil supply
Cause Check Corrective action
Pump not running Check prime mover for operation Repair or replace prime mover
Insufficient oil in reservoir Check fluid level in reservoir Fill with clean filtered oil
Leaking or burst supply hose Inspect lines to valve stack Repair or replace damaged hose
Relief valve malfunction Check for contamination and operation of relief valve Repair or replace relief valve
Isolating valves are closed Check that all isolating valves are open and clear
Faulty pump control Check pump compensator for correct operation and
Low standby pressure in PVP - open
center pump
Low standby pressure in pump
control - variable pump
PVP pressure relief valve faulty Check pressure relief valve spool and spring for
PVP orifices blocked Check PVP orifices for blockage Remove blockage
Internal filters blocked Check for blockage in internal filters Remove blockage
Supply lines blocked Inspect supply lines for blockages Remove blockage
Internal hydraulic pilot pressure
insufficient
Blocked LS galleries Check LS galleries for blockage Clean blockage from LS galleries
Shuttle valves faulty Check LS system shuttle valves for wear and damage Replace as needed
Check feedback pin for damage Replace PVE
Fill reservoir with clean filtered fluid per OEM
specification
controller to the valve section module
controller
Check condition of drive coupling Repair or replace drive coupling
setting per pump manufacturers
Check idle standby pressure - 10 Bar [145 PSI] Replace
Check condition of compensator spool spring Replace module due to worn components
Check pump LS control for operation and setting
Stand by pressure should be 15 bar [220 psi]
minimum
freedom of operation
Inspect pilot oil pressure reducing valve for proper
operation
Bleed air from the hose connection at the valve section
Repair or replace cylinder/motor
specification
Repair or replace pump compensator per pump
manufacturers recommendations
Repair or replace LS control per pump manufacturers
procedures
Replace
Repair or replace
Check for contamination per specification HPP 030. Refer to Design Guideline for Hydraulic Fluid
Cleanliness, Technical Information Manual 520L0467. If fluid is out of spec., flush hydraulic system and fill
with clean filtered oil.
Electrical supply
Cause Check Corrective action
No electrical power Check electrical circuit Repair as needed
Verify emergency stop switch is in the proper operating position Reset
Neutral position switch faulty Check operation of neutral position switch in remote controller (if
connected in circuit) PVRE/PVRES/PVREL
Replace switch
18 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
Service Manual
PVG 32 Proportional Valve Group
System Troubleshooting
Cause Check Corrective action
Incorrect signal voltage Check voltage levels at solenoid plug
Proportional operation - Refer to Troubleshooting Considerations
Udc: Supply voltage (100%)
Us: Supply signal voltage (25-50-75%)
Ground: Live or ground connection
On-Off Operation
Udc: Supply voltage if selected
Us: Supply voltage if selected
Ground: Live or ground connection
Solenoid valve faulty PVHC Check coil resistance Check data for resistance
Insufficient pilot supply Check pilot pressure - 10-15 bar [145-218 psi]/PVHC 25 bar [360
Main spool position feedback
transducer signal incorrect
Incorrect PVE connections Check that the proportional remote electrical controller has not
psi]
Test oil for contamination and or water content If oil contamination is too high, flush hydraulic
been connected to an ON-OFF PVEO solenoid
Replace
system or replace oil if necessary. If problem
persists change PVE
Connect wires correctly
Hydraulic (remote) pilot control pressure
Cause Check Corrective action
Insufficient pilot pressure Check pilot oil pressure 5-15 bar [72-220 psi] delta between A and
Insufficient pilot oil supply Check pilot oil flow rate is adequate
Air in pilot line Check for trapped air in pilot lines Bleed air from pilot lines at PVH
Pilot lines incorrectly sized Check pressure drop Check and reduce length or pilot lines
Hydraulic remote pilot operator
faulty
B port on remote
PVG32: 5-15 Bar [72-217 PSI]
Pilot flow should be 1.0 L/min [0.264 GPM] per section
Check pilot lines for blockage Remove blockage
Increase diameter of pilot lines
Use steel tube for long pilot line runs
Check operation of hydraulic remote pilot controller Repair or replace
Check supply pressure to hydraulic remote controller - minimum
25 bar [360 psi]
Check and inspect movement of pressure control valve in
hydraulic controller
Check operation of remote hydraulic controller Clean and/or repair as necessary
Repair or replace
Repair per manufacturers procedure, or
replace
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 19
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Pressure relief valve
Description: Adjustable relief valve. Adjustment range 50 Bar [700 PSI] to 350 Bar [5000 PSI].
Location: The relief is in all PVP Inlet modules
Function: Provides maximum pressure setting above pump pressure setting 30 Bar [450 PSI] Delta for
open center and closed inlet sections
Failure mode Cause Corrective action
Will not build pressure Contamination While under pressure, back out to minimum pressure and allow oil
External leaking Damaged seat and poppet Replace complete assembly
Pressure setting is wrong Pressure adjustment backs off (on open
Instability when PC and inlet relief
has too low of a delta between
them
center application)
PC at pump should be set 20 bar below relief
valve
Serviceability: Non serviceable.
Valve removal tool P/N: 155L6485. Torque to 20 Nm [180 lbf•in].
to leak by for approx. 5 seconds and then readjust to correct
pressure - Replace valve
Adjust to model code specification
Adjust to model code specification
Pressure reducing pilot valve
Description: Pressure reducing valve at fixed pressure.
Location: The pressure reducing valve is a option in some PVP Inlet modules.
Function: Provides 10-15 bar [145-218 psi] internal pressure for electrical (PVE) actuators or provide 25
Bar (360 PSI) (PVHC) and supply for external remote hydraulic actuators (HRC). These pressures are only
present when the load pressures are high enough to satisfy the required regulated pressure. The open
center system at low pump flow may only develop 9 Bar (130 PSI)
Failure mode Cause Corrective action
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
Contamination Disassemble and clean
Pump pressure too low - below 9 Bar [130 PSI]
High tank port pressure. Do not exceed 40 Bar
[580 PSI] tank pressure (For PVPs without T0
option)
Oil viscosity 460 mm2/S [2128 SUS] too high
(cold oil or incorrect viscosity oil)
For T0 option only not being connected to
tank or restricted to tank
Internal pressure reducing valve parts
misassembled
Contamination Disassemble and clean
Pump pressure too low - below 20 Bar [290
PSI]
High tank port pressure. Tank pressure should
not exceed 40 Bar [580 PSI] (For PVPs without
T0 option)
Oil viscosity - 460 mm2/S [2128 SUS] too high
(cold oil or incorrect viscosity oil)
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 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
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
20 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
P107 733E
6 mm
25 Nm
[220 lbf•in]
O-ring
Spool
Cone
Spring
Plug
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Serviceability: All internal components can be removed from the cavity, cleaned, inspected and
reassembled back into the valve
1. Use a 6 mm internal hex wrench to remove the plug, and then remove all the other internal
components in the cavity
2. Clean all components with clean solvent
3. Replace any damaged components. Lubricate with clean hydraulic oil
4. Correctly reassemble the components back into the cavity and torque the plug to 25 Nm [221 lbf•in]
(use an M5 screw to install spool).
Pressure reducing pilot valve
Pressure gauge connection
Description: Port to install a pressure gauge to check pressure relief valve setting to valve specification.
Location: On inlet cover to valve stack.
1. Use a 6 mm internal hex to remove and install plug.
Failure mode Cause Corrective action
Leaking Bad seal Replace with new seal (same type as original seal)
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Danfoss | February 2017 11039167 | AX00000031en-US0301 | 21
2. Torque plug to 35 Nm [308 lbf•in].
P107 735E
Pressure gauge port
P107 734E
PVPC with check valve
Tee into pressure port
to measure pressure
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Pressure gauge port
When valve is equipped with the PVPC option use a running tee to measure pressure. Torque tee to hose
adaptor torque specification.
PVPC with check valve
Open center plug
Description: Plug that is installed in the inlet cover for a system with a fixed displacement pump.
Location: In the PVP module (Inlet cover).
Function: Connection for the load sense signal to shift the unloading spool to build main system
pressure and provides a connection to the main system relief valve.
Failure mode Cause Corrective action
Valve operates at system relief
setting at all times
22 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
Open center plug is not seated properly Reinstall plug and torque to 4 Nm [35 lbf•in] using a 3 mm internal
hex wrench
P107 736E
Open
center
plug
Plug
Seal
washer
6 mm
35 Nm
[308 lbf•in]
3 mm
4 Nm
[35 lbf•in]
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Serviceability: Open center plug is serviceable.
1. Use a 6 mm internal hex to remove cavity plug from valve.
2. Use a 3 mm internal hex to remove open center plug.
3. Clean or replace open center plug.
4. Install open center plug.
5. Torque plug to 4 Nm [35 lbf•in].
6. Install new seal washer and install cavity plug. Torque to 35 Nm [130 lbf•in].
Open center plug
Closed center plug and orifice
Description: Plug that is installed in the inlet cover for a system with a variable displacement pump.
Location: In the PVP module (Inlet cover).
Function: Allow connection for the load sense signal to the pump and provide connection to the main
system relief valve.
Failure mode Cause Corrective action
Valve operates at system relief
setting at all times
Can not adjust main relief above
pump pressure setting of 30 Bar
[450 psi] Delta for closed inlet
sections
Plug and orifice are not seated properly
Orifice is plugged Remove and clean orifice. Reinstall
Reinstall orifice and torque to 4 Nm [35 lbf•ft] using a 3 mm
internal hex wrench.
Reinstall plug and torque to 8 Nm [71 lbf•in] using a 8 mm internal
hex wrench
Serviceability: Closed center plug and orifice are serviceable.
1. Use a 6 mm internal hex to remove cavity plug from valve.
2. Use a 4 mm internal hex to remove closed center plug.
3. Use a 2.5 mm internal hex to remove orifice.
4. Clean or replace orifice. Install orifice. Torque to 4 Nm [35 lbf•in].
5. Install new seal and install closed center plug. Torque to 8 Nm [71 lbf•in].
6. Install new O-ring and install plug. Torque to 35 Nm [130 lbf•in].
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Danfoss | February 2017 11039167 | AX00000031en-US0301 | 23
P107 737E
Closed
center
plug
Plug
O-ring
Seal
Orifice
6 mm
35 Nm [308 lbf•in]
4 mm
8 Nm
[70 lbf•in]
2.5 mm
4 Nm
[35 lbf•in]
P107739E
Pressure adjustment spool
Orifice
Plug
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Closed center plug
Pressure adjustment spool
Description: Main pump flow unloading spool.
Location: PVP (inlet) module.
Function: For open center systems it is the main relief and unloading spool
For closed center systems it is the main relief spool.
Failure mode Cause Corrective action
In open center systems the valve
sections are unstable
The adjusted pressure will not
remain static in a closed center
system
High wear allows leakage to tank Replace compete module
Low viscosity oil allowing high leakage
around spool to tank.
High wear Replace compete module
Remove and clean orifice. Reinstall
Serviceability: Spool is not serviceable. Replace complete module.
Pressure adjustment spool
24 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
P107 740E
LS Plug
6 mm
35 Nm [308 lbf•in]
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
LS connection
Description: Port for LS signal for LS (static) option only controller for variable flow pump.
Location: PVP (inlet) module.
Function: Provide a signal to the variable pump controller to create a pressure differential to have the
pump come on stroke for a closed center system.
Failure mode Cause Corrective action
In closed center systems the valve
sections are unstable
Valve operation is slow to respond
or does not respond
Insufficient LS flow to satisfy pump controller
Excessive air entrained in the hydraulic oil Ensure that the oil has enough dwell time in tank, has good anti-
Air trapped in LS line Bleed air for LS line at highest point
Insufficient LS flow to satisfy pump controller If more than one section, ensure that the LS controller on the
Excessive air entrained in the hydraulic oil Ensure that the oil has enough dwell time in tank, has good anti-
Air trapped in LS line Bleed air for LS line at highest point
Ensure that the LS controller on the pump does not have excessive
internal leakage - 0.4 l/min [0.106 gal/min]. Repair or replace the
variable pump controller per pump manufactures specifications
If there is more than one valve in the system ensure that the LS
shuttles are all working properly
foaming agent, and pump inlet vacuum is within manufacturers
specifications
pump does not have excessive internal leakage. Repair or replace
the variable pump controller per pump manufactures
specifications
foaming agent, and pump inlet vacuum is within specifications
PVG valve is mounted above hydraulic oil reservoir when shut down and sits idle for some time, the valve
could be voided of oil and this would cause the valve to operate erratically and be slow to respond.
Serviceability: Port is serviceable. Need to connect hose to LS port on pump.
LS connection plug
LS signal
Description: The PVG32 uses an internal LS signal network for both Open Center and Closed Center
systems. In Open Center systems the internal LS signal network provides a resolved load sense signal to
the pressure adjustment spool controlling the proper amount of flow and pressure to the operating valve
sections. In Closed Center systems the internal LS signal network provides a resolved load sense signal
directly to the LS pump control which in turn provides the proper amount of flow and pressure to the
operating valve sections.
Location: PVP/PVB Modules.
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Danfoss | February 2017 11039167 | AX00000031en-US0301 | 25
10. Shuttle valve
PVP
PVB
PVB
P107 815E
LS
circuit
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Function: Directs the highest load pressure to either OC or CC pump control to satisfy the operating
valve section.
Failure mode Cause Corrective action
No pump pressure developed in
one or more valve sections
LS passages blocked or restricted Disassemble valve. Inspect passages for blockage
Serviceability: Not serviceable. Ensure entire system is clean.
LS circuit
Shuttle valve
Description: Self cleaning internal shuttle system.
Location: PVB (valve section) module.
Function: Determines which valve section is developing highest load pressure.
Failure mode Cause Corrective action
Valve sections will not build
pressure (NOTE: Normally it will be
one section, but not all sections)
Worn shuttle disc Replace complete module (seat is pressed into module)
Excessive air entrained in the hydraulic oil Ensure that the oil has enough dwell time in tank, has good anti-
foaming agent, and pump inlet vacuum is within specifications
Serviceability: Not serviceable. Ensure entire system is clean.
26 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
P107 804
Exploded view shows internal parts.
Do not disassemble valve.
Ball should move
freely behind disk.
Ball should move
freely behind disk.
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Shuttle valve
LS pressure limiting valve
Failure mode Cause Corrective action
Section will not build pressure in
one spool direction
External leaking Low cartridge torque
Pressure adjustment backs off Adjust pressure to valve specifications If adjustment doesn’t hold, replace valve
LS A, B shuttle
Description: Optional adjustable pilot relief valve.
Location: PVB (spool body section) module.
Function: Controls the maximum working pressure delivered to each work port.
There is one LS pressure limiting valve for each work port.
Contamination While under pressure back out to minimum pressure and allow oil
to leak by for approx. 5 seconds and then readjust to correct
pressure - Ensure system is clean - Replace PVB
Torque to 20 Nm [177 lbf•in] maximum
Replace complete assembly
Serviceability: Adjustable and non-serviceable. If adjustment does not solve the problem, replace
complete cartridge.
Valve removal tool P/N: 155L6485. Torque to 20 Nm [177 lbf•in].
Description: The shuttle valve isolates the LS(A) and LS(B) load sense signal.
Location: Option PVB module with only load sense relief.
Function: Ensure that each pressure limiter valve can create separate pressures for A and B LS signal.
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 27
Shuttle
ball
P107 821
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Failure mode Cause Corrective action
Will not build pressure in A or B
work port
Contamination preventing shuttle ball from
building load sense relief pressure
LS A, B shuttle
Replace complete PVB module
Main spool
Description: Main directional control.
Location: PVB (valve section) module.
Function: Controls oil flow from pump to work ports A or B.
Failure mode Cause Corrective action
Section will not build pressure in one
spool direction
Main valve spool stuck in valve body
(if being used with electrical
actuator)
Mechanical actuator main valve
spool stuck in valve body
Main spool stuck in valve body Tie rod over torqued Replace tie rod kit which includes section seals and torque to 28
Load sense passages in spool are blocked Flush out load sense passages in the spool. Spool will need to be
Refer to Pressure reducing valve Replace PVM and PVE. Be sure that pilot valve is assembled
Hard particle binding spool in bore
Valve stack mounting surface is not flat
causing a bind on the valve stack
removed to clean
correctly.
Look down into the A and B work ports to see if the particle can
be removed while the spool is in the valve body. Replace valve
section.
NOTE: Valve body and spool will need to be replaced per valve
specifications
Nm [248 lbf•in]
Ensure the mounting surface is flat*
* Flatness in millimeters - T= 0.35 mm X number of PVB modules + 1
Serviceability: Main spool is serviceable depending on failure mode.
1. Remove manual actuator using a 5 mm internal hex wrench to remove the 4 mounting screws.
CAREFULLY place the main spool in to an appropriate fixture or vice with card board, rubber hose or
heavy shop towels on the jaws and tighten just enough to keep the spool from turning in the vice.
DO NOT over tighten the main spool in the vice as it will be distorted and or scratched on sealing
lands and the spool will need to be replaced.
2. Remove the tension rod end using a 13 mm open end wrench.
3. Remove the plug at the other end using an 11 mm, or if it has a detent option, use a 12 mm open end
wrench.
4. Flush out openings into the main spool cavity at each end.
28 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
P107 805E
Clean holes
11 mm
8 Nm
[70 lbf•in]
Screw
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
5. Install plug with a 11 mm or 12 mm open end wrench. Torque to 8 Nm [70 lbf•in].
6. Install centering spring and tension rod using a 13 mm open end wrench and torque to 8 Nm [70
lbf•in].
7. Carefully reinstall the main valve spool into the valve housing. Do not force the main spool back into
the housing as you will damage the sealing lands in the valve housing. The spool should move freely
in the main spool bore when fully installed.
8. Install a manual actuator. Reassemble in reverse order and torque the 4 mounting screws to 8 Nm [70
lbf•in]
If section does not build pressure in one direction, wrong spool may have been installed in valve.
Main spool
Shock and anti-cavitation valve PVLP
Description: Optional work ports non adjustable pressure relief valve.
Location: PVB (valve section) Module.
Function: Removes any transient pressure spikes generated by the load.
The shock valves PVLP with fixed setting and the anti-cavitation valves PVLA on ports A and B are used for
the protection of the individual work function against overload and/or cavitation.
There is one shock valve for each work port.
Failure mode Cause Corrective action
Will not build pressure in A or B
port
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 29
Valve may be damaged and not able to seal Replace with correct part number per valve specification
Serviceability: This valve may be disassembled and cleaned, however, internal parts are not available
separately. If you suspect valve malfunction, replace with a new valve and test system operation.
P107 743E
13 mm
36 Nm
[310 lbf•in]
Plug
Do not try to adjust
or disassemble PVLP
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVLP valve
Pressure compensator
Failure mode Cause Corrective action
Valve section unstable flow High wear allows leakage Replace complete module
LS pressure limiting valve pressure adjustment
will not remain static
Description: Optional pressure compensator maintains a constant pressure drop across the main spool.
Location: PVB (Valve section) Module.
Function: In a pressure-compensated basic module the compensator maintains a constant pressure drop
across the main spool – both when the load changes and when a module with a higher load pressure is
actuated.
High wear Replace complete module
Serviceability: Pressure compensator is not serviceable. If you suspect valve malfunction, replace
complete module.
30 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
P107 744E
Pressure compensator spool
P107 822
Pressure compensator spool
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Pressure compensator valve
Load drop check valve
Failure mode Cause Corrective action
Load drops excessively when
trying to lift load
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 31
Description: Keeps the load from dropping when transitioning from spool neutral to lifting the load.
Location: PVB (valve section) module.
Function: Optional drop check to keep the load from dropping. Prevents high pressure functions from
supplying low pressure functions when both are actuated simultaneously.
Worn parts. Replace complete PVB module
Hard particle in seat area does not allow the
seat to seal
Replace complete module
Serviceability: Load drop check valve is not serviceable. If you suspect valve malfunction, replace
complete module.
P107747E
Load drop check valve
P107 748E
Load drop check valve
C
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Load drop check valve
Maximum oil flow adjustment screws for ports A and B
Description: Optional mechanical flow limiter.
Location: PVM manual control handle.
Function: Determines the stroke of the main spool in the PVB.
Failure mode Cause Corrective action
Cylinder/motor functions too slow
or too fast
Leaking past adjusting screws Check torque on seal nut 8 Nm [71 lbf•in] Retorque or replace seal nuts
Mechanical stop screws out of adjustment per
valve spec.
Caution
When adjusting main spool flow ensure that electrical or hydraulic actuators are not active at the time, if
so equipped.
Use a 8mm open end wrench to loosen the jam nut and then 3mm
internal hex wrench to adjust the mechanical adjusting screw CCW
to increase speed. After adjusting hold the adjusting screw and
torque the jam nut to 8 Nm [70 lbf•in] maximum
32 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
P107 816E
For standard mount, top adjusting screw is B
and bottom adjusting screw is A
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Adjusting screws for ports A and B
PVM module
Failure mode Cause Corrective action
Leaking externally between PVM
and PVB
Description: Manual control lever.
Location: Mounted on either end of the PVB main spool.
Function: Manual override capable of limiting the stroke of the main spool, and is used to center the
spool in neutral.
Back pressure is exceeding 40 Bar [580 PSI] on
tank line
T0 port not connected to tank or restricted or
blocked
Replace PVM module, seals, and lower tank port pressure
Connect to tank, remove restriction, and remove blockage
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 33
P197 806E
O-rings
Seal
Screw (x4)
5 mm
8 Nm [70 lbf•in]
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVM module
PVS module
Description: End cover.
Location: Mounted on the last PVB of the valve stack.
Function: Serves as blanking cover and drain for LS circuit.
Failure mode Cause Corrective action
Leaking externally between PVS
and PVB
Back pressure is exceeding 40 Bar [580 PSI] on
tank line
Maximum pressure:
Aluminum - 300 bar [4500 psi]
Steel - 350 bar [5000 psi]
Replace PVS module, seals, and lower tank line pressure
Reduce system pressure
34 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
P107 707E
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVS plugs
For specifications and operating parameters on PVG 32 valves, refer to PVG 32 Technical Information
Manual 520L0344.
PVPVM module
Description: Mid-inlet module only for closed center systems.
Location: Mounted between multiple PVB’s in a valve stack.
Function: Provides pressure and tank connections to the valve stack allowing increased flow.
Failure mode Cause Corrective action
Leaking externally between
PVPVM and PVB
Valve stack can not build pressure
per valve spec.
Uneven mounting surface and mounting
screw torque
Tie rods torqued too tight Replace tie rod kit which include section seals and torque to 28
Flow exceeding 61 gpm Lower flow to 61 gpm, and replace the tie rod kit and seals
Option PVLP (shock valve) not seating
correctly in cavity caused by valve not being
installed correctly or it has failed
Ensure the valve stack is mounted on a even surface and torque
down correctly
Nm [248 lbf•in]
Install components correctly or replaced damaged components
* Flatness in millimeters - T= 0.35 mm X number of PVB modules + 1
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 35
P107 808E
13 mm
40 Nm
[354 lbf•in]
Plug
Do not try to adjust
or disassenmble PVLP
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVPVM module
PVAS module
Description: Tie rod kit.
Location: Through the valve stack.
Function: Holds the stack together.
Failure mode Cause Corrective action
Leaking externally between
sections
36 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
Tie rods under torqued Check and retorque - 28 Nm [248 lbf•in]
Tie rods torque too tight Replace and retorque - 28 Nm [248 lbf•in]
P107 817E
If replacing seal kit,
replace tie rods also
8
-
248
-
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVPX LS unloading valve
Refer to PVPX Electrical LS unloading valve for valve operation.
Description: Optional two way two position solenoid.
Location: In the PVP.
Function: A safety device that dumps load sense to tank to prevent the pump from building pressure.
Failure mode Cause Corrective action
Manual override leaking externally Not torqued correctly Check and retorque to 45 Nm [400 lbf•in]
High usage Replace per valve specification
Manual override is bent Replace per valve specification
Solenoid will not shift Coil not working
Too high or too low of voltage
Replace coil per valve specification
Check with OHM meter:
12 volt system - 8.7 OHMs
24 volt system - 33 OHMs
Confirm voltage in system from remote controller:
12 volt system should not exceed 13.2 volts
24 volt system should not exceed 26.4 volts
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 37
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVEM, PVEA, PVEH, PVES electrical actuators
Description: Proportional electrical actuator.
Location: On the end of the main spool of the PVB.
Function: Convert an electrical command to move the main spool to a set position.
Troubleshooting Considerations
Wiring Check: It is highly possible that in the case of one PVE failing that there could be a poor
connection between the joystick and the PVE in question. The PVE is reverse polarity protected and
suppression protected; however an intermittent connection could degrade the input electronics to a
point of failure. Inspect all wiring and connectors for corrosion and or pinch points.
Hirshman Receptacle and Mating Connector: Each PVE is supplied with a field installable 4-pin
Hirshman mating connector and gasket. It is recommended that the gasket be installed between the
mating connector and PVE receptacle also the rubber grommet be sealed around a multi-wire jacket in
order to seal off moisture from the wiring connections. The PVE is rated for IP65 only when the Hirshman
connector is sealed.
Temperature Capability: The PVE ambient temperature range is rated at -40 to 90 °C. Oil temperature
wise, the area of the valve that creates the highest horsepower loss usually creates the highest
temperature in the system. If one PVE section is operated more frequently than others this would create
more heat than any other part of the valve. Under these conditions it is extremely important to insure
that the hydraulic system is well cooled. Oil temperature measurements at the reservoir and at the center
of the PVG32 valve stack. The valve should be mounted to provide the best ventilation for the PVE
electronics. Poor filtration and low fluid levels may also add to temperature.
Troubleshooting
Failure mode Cause Corrective action
Does not work in either direction
LED is green
Does not work in either direction
LED is off
LED is flashing Red Control signal is out of range Check wiring harness for short
Works in one direction (Assuming
that the manual control lever and
the main spool move freely both
directions)
Works intermittently (if LED is
green it indicates a long on/off
Works with no command from
controller
No control voltage from the electrical controller Check voltage from the electrical controller (25% to 75% of
Command pin wire in mating connector is broken Repair broken wire
Connector corroded - This condition is caused by
water ingression or ground connection
No power from the battery Check power to electrical actuator
Power pin wire in mating connector is broken Repair broken wire
Connector corroded - This condition is caused by
water ingression or ground connection
Ground connection must be hard wired straight from
the battery or from the electrical controller
No control voltage from the electrical controller Ensure voltage from the electrical controller exists for that
Lack of voltage to actuator (Minimum voltage 11
volts for 12 volt system and 22 volts for 24 volt
system)
Electrical actuator is defective Replace electrical actuator per spec. on the valve
Loose connection between the electrical actuator and
controller
Electrical actuator is defective Replace electrical actuator per spec. on the valve
Short in wiring harness Repair wiring harness
Short in wiring harness Repair wiring harness
Electrical actuator position feed back out of
adjustment
Fine particulate contamination Replace PVE or electric actuator per valve specs.
supply)
Replace PVE and mating connector
Replace PVE and mating connector
Repair ground connection
direction
Check system voltage
Repair connector
Replace the electrical actuator per valve spec.
38 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Checking input control signal:
1. Install volt meter to ground pin connection and signal pin with PVE in circuit.
2. Turn the power on for the electrical controller.
3. Actuate the electrical controller and read the voltage.
4. The control voltage should be per the electrical controller output signal.
On electrical actuators - coil resistance can not be measured at the pins.
When replacing an electrical actuator be sure that it has the same part number on it to ensure original
functionality.
If filter in the electrical actuator has pieces of contamination trapped in it, this is a good indication that
the complete system is contaminated and needs to be flushed. The filter in the electrical actuator can be
removed and cleaned.
PVEO ON/OFF electrical actuator
Description: ON/OFF electrical actuator.
Location: On the end of the main spool of the PVB.
Function: Convert an electrical command to move the main spool to a set position.
Troubleshooting
Failure mode Cause Corrective action
Does not work in either direction No control voltage from the electrical
Works in one direction
(Assuming that the manual control
lever and the main spool moves
freely both directions)
Works intermittently Loose connection between the electrical
Works with no command from
controller
controller
Command pin wire in mating connector is
broken
Connector corroded
24 volt electrical actuator used on a 12 volt
system
No power from the battery Check power to electrical actuator
Power pin wire in mating connector is broken Repair broken wire
Ground connection must be hard wired
straight from the battery or from the electrical
controller
No control voltage from the electrical
controller
Lack of voltage to actuator
(Minimum voltage 11 volts for 12 volt system
and 22 volts for 24 volt system)
Electrical actuator is defective Replace electrical actuator per spec. on the valve
actuator and controller
Electrical actuator is defective Replace electrical actuator per spec. on the valve
Short in wiring harness Repair wiring harness
Fine contamination Replace the electrical actuator per valve spec. and flush the
Short in wiring harness Repair wiring harness
Check voltage from the electrical controller
Resistance check (measures between pin 2 and ground):
17 OHMs for 12 volt systems
63 OHMs for 24 volt systems
Repair broken wire
Replace PVE and mating connector
This condition is caused by water ingression or ground connection
Replace with the correct electrical actuator for a 24 volt system
Repair ground connection
Check voltage from the electrical controller is there for that
direction
Check system voltage
Repair connector
complete system and fill with filtered oil
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 39
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
Checking input control signal
1. Install a volt meter to the ground pin connection and to the signal pin.
2. Turn the power on for the electrical controller.
3. Actuate the electrical controller and read the voltage.
4. The control voltage should be per the electrical controller output range.
PVE Series 4/7 Connectors
PVEO/PVEO-R/PVEO-HP
Connector Pin 1 Pin 2 Pin 3 Pin 4
1x4 AMP Udc_A Udc_B GND GND
1x4 DEU Udc_A GND GND Udc_B
1x4 DIN Udc_A Udc_B GND
PVEO-DI
Connector Pin 1 Pin 2 Pin 3 Pin 4
2x4 AMP (A) Udc_A Udc_B GND GND
2x4 AMP (B) DI-B DI-A GND Udc
2
PVEM
Connector Pin 1 Pin 2 Pin 3 Pin 4
1x4 DIN Udc Us Error GND
PVEA/PVEH/PVES
Connector Pin 1 Pin 2 Pin 3 Pin 4
1x4 AMP Us Udc GND Error
1x4 DEU Us Error GND Udc
1x4 DIN Udc Us Error GND
PVEA-DI/PVEH-DI
Connector Pin 1 Pin 2 Pin 3 Pin 4
2x4 AMP (A) Us Udc GND Error
2x4 AMP (B) DI-A DI-B GND Udc
2x4 DEU (A) Us Error GND Udc
2x4 DEU (B) Udc
2
GND DI-A DI-B
2
PVEH-FLA
Connector Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6
1x6 AMP Us Udc GND Error Float
1x6 DEU Us Error Float GND Udc
PVEH-SP/PVES-SP
Connector Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6
1x6 DEU Us Error SP GND Udc
40 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
2
3
4
1
1
2
3 4
5
6
3
4
1
2
1
2
3
4
A
B
1 2
3
4
2418
1
2
3
4
1
2
34
5
6
1
2
3
4
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVEP
Connector Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6
1x6 DEU PWM_A Error PWM_B Udc GND
PVED-CC
Connector Pin 1 Pin 2 Pin 3 Pin 4
2x4 AMP (A/B) CAN_L Udc GND CAN_H
2x4 DEU (A/B) CAN_H CAN_L Udc GND
PVE Series 5 Connectors
PVED-CC
Connector Pin 1 Pin 2 Pin 3 Pin 4
2x4 AMP (A/B) CAN_L Udc GND CAN_H
2x4 DEU (A/B) CAN_H CAN_L Udc GND
Connector diagrams
1x4 DEU
1x4 AMP
1x6 DEU
1x6 AMP
2x4 DEU
1x4 DIN
2x4 AMP
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 41
P107 734E
PVPC with check valve
Tee into pressure port
to measure pressure
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVPC plug for external pilot control
Description: Pilot oil supply from another pump.
Location: On the end of the PVP.
Function: Provides a hydraulic pilot supply to the valve stack.
Failure mode Cause Corrective action
Main spool moves slow, or not at
all, in all sections
External hydraulic pilot pressure is too low Check external hydraulic pressure from pilot pump and/or
restrictions
PVPC plug for external pilot
PVMR Friction Module
Description: Mechanical friction hold.
Location: Mounted on main spool in the PVB.
Function: Infinite mechanical positioning of the main spool.
Failure mode Cause Corrective action
Flow changes Excessive flow across the main spool Reduce flow (100 l/min or less)
Vibration Reduce vibration
Broken spring Replace broken springs
Flow changes or will not stay in
detent
Check for proper assembly of parts Install parts correctly per specification sheet
42 | © Danfoss | February 2017 11039167 | AX00000031en-US0301
P107 811E
Mechanical detent
11 mm
4 Nm
[35 lbf•in]
Plug (x3)
5 mm
8 Nm
[71 lbf•in]
Screw (x4)
36 mm
15 Nm
[133 lbf•in]
Plug
Service Manual
PVG 32 Proportional Valve Group
PVG 32 Component Troubleshooting
PVMR module
©
Danfoss | February 2017 11039167 | AX00000031en-US0301 | 43
Local address:
Danfoss
Power Solutions GmbH & Co. OHG
Krokamp 35
D-24539 Neumünster, Germany
Phone: +49 4321 871 0
Danfoss
Power Solutions ApS
Nordborgvej 81
DK-6430 Nordborg, Denmark
Phone: +45 7488 2222
Danfoss
Power Solutions (US) Company
2800 East 13th Street
Ames, IA 50010, USA
Phone: +1 515 239 6000
Danfoss
Power Solutions Trading
(Shanghai) Co., Ltd.
Building #22, No. 1000 Jin Hai Rd
Jin Qiao, Pudong New District
Shanghai, China 201206
Phone: +86 21 3418 5200
Comatrol
www.comatrol.com
Turolla
www.turollaocg.com
Hydro-Gear
www.hydro-gear.com
Daikin-Sauer-Danfoss
www.daikin-sauer-danfoss.com
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already on order provided that such alterations can be made without changes being necessary in specifications already agreed.
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©
Danfoss | February 2017 11039167 | AX00000031en-US0301
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