MTS Model 512-01 Hydraulic Power Unit - Manual (Page 22)

Model 512.01 Hydraulic Power Unit 22 Maintenance
Resetting the Thermal Overloads
The thermal overloads of the hydraulic power unit (HPU) can be tripped
by the following conditions:
• Poor motor ventilation
• The output pressure is set too high
• A pump or motor is seizing
The thermal overloads are located in the control box.
Do not open the control box unless the line voltage is turned off. When
power is present in the control box, high voltage and amperages are also
present.
You can be electrocuted if you touch the wrong component in the control
box.
Disconnect the HPU from power before opening the control box.
1. Press RESET on the control box cover.
• If it’s tripped, reset it and try restarting the HPU.
• If it trips again, turn the
HPU off before opening
the control panel.
2. Disconnect the HPU from its
electrical power source.
3. Unscrew the clamps holding
the control panel’s door shut.
4. Check for a blown fuse. A
defective varistor can also
cause this fuse to blow. The
replacement fuse must have
the same rating as the blown
fuse.
5. Shut the control box door. Use
the clamps to hold it in place.
6. Reconnect the HPU to its electrical power source.
7. Restart the HPU. If the HPU will not restart or shuts down right away,
call MTS.
WARNING
Jumper
Plug
Fuse
Varistor