Instruction Sheet ZU4 Classic Torque Wrench Pump - Enerpac

5.0 OPERATION
5.1 Pump On-Off Switch (See Figure 6)
On-Off Switch positions:
1. ON - Pump controlled by pendant. Pump starts when pendant
“ON/ADV” button is depressed.
2. OFF - Pendant disabled. Pump will not start when pendant
“ON/ADV” button is depressed.
Circuit Breaker: If tripped, press button to reset.
Pendant On-Off
Switch
Figure 6, Pump Control Panel
5.2 Pendant Operation (See Figure 7)
1. Pendant “ON/ADV” Button:
• Button depressed - Motor turns ON. Wrench ADVANCES
for as long as button is held down.
• Button released - Wrench RETRACTS. Motor continues
running for up to 20 seconds.
2. Pendant “OFF/DUMP” Button:
• Button depressed - Motor turns OFF immediately.
Note: Immediate motor shutoff will occur if the pump on-off switch
is moved to OFF while the pump is running.
Pendant ON/ADV Button
Pendant OFF/DUMP Button
Figure 7, Pendant Buttons
4
5.3 Pump Operation
IMPORTANT: When possible, a single user should operate the
torque wrench and pump. This can prevent accidental activation
of the pump while the operator is positioning the wrench.
1. Check all system fi ttings and connections to be sure they are
tight and leak free.
2. Check oil level in reservoir and add oil if necessary. (see
section 4.4)
3. Make sure the shipping plug has been removed and the
breather cap is installed. (see section 4.1)
4. Connect unit to power. Move the pump on-off switch to ON.
See Figure 6.
WARNING: In the following step, the pump motor will
start and the valve will shift automatically, retracting
the torque wrench. Verify torque wrench is positioned
to avoid injury or equipment damage before starting motor.
5. To start the pump, press the “ON/ADV” button on the
pendant. See Figure 7. The motor will start automatically,
and the wrench will begin to advance. The wrench will
continue advancing for as long as the button is held down.
6. Release the “ON/ADV” button to retract the wrench. After
button is released, the gauge will show the pressure in the
retract circuit (B-port bypass), approximately 2500 - 2800 psi
[173-193 bar].
7. Press the “OFF/DUMP” button to stop the motor.
Note: If the "ON/ADV" button is not pushed within any continuous
20 second period, the pump's built in timer will automatically
shut off the motor.
8. To release hydraulic pressure on the wrench and hoses, press
and hold the “OFF/DUMP” button AFTER the motor is turned
off. The hoses can now be removed.
Note: Units equipped with heat exchangers: When practical,
allow the timer to automatically shut-off pump. During any idle
period, the pump is circulating 90% of its oil fl ow through the heat
exchanger to reduce oil temperature.
5.4 Gauge and Overlay Operation Procedure
The pump is supplied with a pressure gauge installed. For your
convenience, torque overlays are provided with each pump. A
torque overlay fi ts over the pressure gauge dial face and easily
converts pressure readings to torque readings (see Fig. 8, View
A). The overlay has imperial units (Ft-Lbs.) on one side and metric
units (Nm) on the other. To change scales simply slip overlay over.
WARNING: Each overlay is sized for a specifi c
Enerpac torque wrench ONLY. Do not use with other
wrenches.
5.5 Changing the Overlay
1. Remove the three black wing knobs which hold the front
gauge fl ange in place (see Fig. 8, View B).
2. Remove the front fl ange and overlay (see Fig. 8, View C).
3. Insert new overlay (remember to verify correct overlay to the
Enerpac torque wrench being used) onto the fl ange, aligning the
overlay with the dimples on the back of the fl ange (see Fig. 8,
View D).