User Manual

Model 512.04 Hydraulic Power Unit Maintenance
21
Maintenance
Contents Reducing the Fluid Temperature 22
Adjusting the Air Flow 23
Adjusting the Water Flow 24
Resetting the Thermal Overloads 26
Changing the Output Pressure 27
Lubricating the Motor 29
Changing the Filter 30
Changing the Hydraulic Fluid 31
Abnormal
shutdowns
Any one of the following can cause your HPU to suddenly shut down. You
will not be able to restart your HPU until you correct the condition.
Maintenance Intervals
W
HAT TO DO WHEN TO DO IT
Recover from an abnormal shutdown As needed–when the HPU suddenly stops running.
Lower the output pressure As required by your test needs.
Adjust the heat exchange louvers When you can not maintain a fluid temperature between 64
and 68ºC (147 and 158ºF).
Adjust the water control valve When you can not maintain a fluid temperature between 64
and 68ºC (147 and 158ºF).
Lubricate the pump motor Every six months.
Change the filter When the filter gage needle stays in the yellow or red zone;
whenever you change hydraulic fluid.
Change the fluid If the fluid’s condition becomes poor, or fluid analysis shows it
is necessary.
PROBLEM SOLUTION
The hydraulic fluid exceeds
75ºC (160ºF).
See “Reducing the Fluid
Temperature” on page 22.
The hydraulic fluid cannot be seen in
the sight glass (or it is at a low level).
See “Adding Hydraulic Fluid” on
page 25
.
A tripped thermal overload or blown
fuse in the control box removed
power from the unit.
See “Resetting the Thermal
Overloads” on page 26.