Enerpac PU-Series - Manual (Page 5)

5
5.2 Pump Control Valve PUJ-1200B/E and PUJ-
1201B/E models
The pump control valve directs hydraulic fluid output or return
from the hydraulic system components. These models have 3
way, 2 position valves. Valve positions are shown in Figure 8: (1)-
Advance; (3)-Retract.To advance the cylinder, shift the valve to the
advance position (1) and press the pendant switch.
The cylinder will advance until the pendant switch is released.
To retract the cylinder, shift the valve to the retract position (3).
The cylinder will retract with or without the pump running.
PUJ 1400B/E and PUJ-1401B/E Models (Figure 8)
Control valves on PUJ-1400B/E and PUJ-1401B/E pumps are 4-
way, 3-position, for use with double acting cylinders where advance
and retract are hydraulically actuated. Valve positions are shown in
Figure 8: 1-Advance; 2- Retract; 3- Neutral. In each position the
cylinder movement is controlled by the pendant switch.
Figure 8
PUD-1100B/E and PUD-1101B/E Models
The PUD-1100B/E and PUD-1101B/E operate single-acting
cylinders where the hold function is not necessary. Pressing the
pendant switch starts the motor and advances the cylinder. When
the switch is released, the cylinder will retract.
PUD1300B/E and PUD1301B/E models
The PUD1300B/E and PUD1301B/E operate single-acting
cylinders where the hold function is required. Press the advance
button to start the pump and advance the cylinder.
Releasing the advance button will stop the pump and the cylinder
will hold the load with the valve. Pressing the retract button will
shift the valve, allowing the load to retract.
NOTE: Because the time for the motor to stop can vary,
depending on load conditions, the load may not stop advancing
at the exact time the advance button is released. There may be a
small movement of the cylinder while the motor is stopping.
5.3 Thermal Switch (All models)
To protect the pump from damage, an internal thermal switch
shuts off the motor when the oil temperature reaches 150°F
(65°C). When the temperature drops to 130°F (54°C) the switch
will automatically reset.
5.4 Air Removal
When the hydraulic system is connected for the first time, air will
be trapped in the components. To ensure smooth, safe operation,
remove the air by running the system through several complete
cycles without a load on the cylinders. When cylinders advance
and retract without hesitation, the air is vented from the system.
WARNING: To avoid injury and equipment damage, do
not continue pressurizing cylinders after they reach
maximum travel or maximum operating pressure.
6.0 RELIEF VALVE ADJUSTMENT (Figure 9)
The main pump relief valve is internal and non-adjustable, factory
set for 10,000 psi (700 bar) maximum operating pressure. An
additional external relief valve is located under a hex cap on the
right side of the pump. The external relief valve is adjustable from
10,000 psi (700 bar) down to 2000 psi (140 bar). Operating
pressure limits can be reduced below 10,000 psi (700 bar), but not
above 10,000 psi (700 bar). (PUJ-1400B/E and PUJ-1401B/E
models are not equipped with external adjustable relief valves.)
1. Install a gauge as directed in the installation instructions on
page 3.
2. Install a plug in the valve outlet port.
3. Remove the hex cap (H) covering the relief valve adjustment
screw.
4. Using an allen wrench, turn the adjustment screw
counterclockwise one full turn.
5. Turn the pump "ON" and run the pump motor, watching the
gauge reading for the maximum pressure. Stop the pump.
6. Continue to adjust the setting until the desired pressure is
attained.
7. Check the setting by running the pump several times. If the
gauge reading is the same each time, the valve setting is
stable.
8. Replace the hex cap to cover the adjusting screw.
Figure 9
NOTE: To get the most accurate relief valve setting, start at a
lower pressure and adjust up to the desired relief valve setting.
WARNING To avoid equipment damage and personal
injury, do not attempt to exceed 10,000 psi (700 bar)
maximum operating pressure.
7.0 MAINTENANCE
7.1 Checking the Oil Level
Check reservoir hydraulic oil level every 40 hours of operation.
Add oil when necessary to bring the level to 1/2" (1 cm) below the
fill opening. Use only Enerpac hydraulic oil. The use of other oils
or fluids may damage your system, and will void your Enerpac
warranty.
7.2 Changing the Oil (Figure 10)
Completely drain the reservoir after every 100 hours of operation.
Refill with new hydraulic oil. If pump is operated in very dusty
areas or at high temperatures, drain and refill more frequently.
1. To drain the reservoir, remove the vent/fill plug (F) from the
top right hand corner of the reservoir.