System Troubleshooting; Overview; Troubleshooting A Pvg Valve - Danfoss PVG 100 Service Manual

Service Manual

System Troubleshooting

Overview

Troubleshooting a PVG Valve

14
PVG 100 Proportional Valves
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
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 100 Technical Information Manual 520L0720 for valve configuration information.
Refer to PVG 100 Parts Manual 520L0888 for part numbers.
W
Warning
This troubleshooting guide for the PVG valve assemblies does not cover valves that have been altered
from original valve build specifications
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 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.
11048807 • Rev BA • October 2014
Introduction section and related to your specific equipment.