Motor Overload Relay - Enerpac Pow'r-Riser Pr-Serie Bedienungsanleitung

6.5 Motor Overload Relay (Three-phase models only)
DANGER: Electric Shock Hazard! High voltage is
present inside the jack even when motor is off . Be sure
that jack power cord is disconnected from the electrical
outlet (or other electrical power source) before removing or
installing fuses or before opening the electrical enclosure door.
Failure to observe this precaution could result in death or serious
personal injury.
Jack models equipped with a three-phase electrical system contain
a resettable motor overload relay. The relay reset button is located
inside the jack electrical enclosure. See Figure 10, Item C.
If the motor overload relay trips, the jack motor will not start
when the pendant buttons are depressed. The trip indicator fl ag
(located on the front of the relay) will also be visible.
To reset the motor overload relay, depress and release the reset
button and verify that the trip indicator fl ag disappears. This
indicates that the relay has been reset.
If the motor overload relay will not reset, wait a few minutes for
the relay to cool and then try resetting it again.
If the motor overload relay continues to trip during normal
operation, have the jack electrical system inspected and repaired
by an Enerpac authorized service center.
Possible Cause
Symptom
1. Sporadic cylinder Air trapped in hydraulic system.
action.
Low oil level in hydraulic reservoir.
Seal wear and/or other internal damage.
2. Noisy operation. Air trapped in hydraulic system.
Low oil level in hydraulic reservoir.
Air leaks in hydraulic system.
Clogged or blocked pump intake screen.
3. Unusually slow Low voltage.
operation.
Extension cord too long.
Extension cord wire gauge not thick
enough.
4. Oil is overheating. Low oil level in hydraulic reservoir.
Oil viscosity too high or too low.
High pressure leakage at the pump.
5. Pump runs but will not Seal wear and/or other internal damage.
pump oil.
OR
Control valve needs repair.
Cylinder moves but
will not lift load.
7.0 TROUBLESHOOTING
The information in the Troubleshooting Guide (refer to Table 10) is
intended as an aid to help diagnose and correct various possible
problems that may occur.
For repair service, contact your local Enerpac authorized service
center. Only an Enerpac authorized service center should service
the jack and its components.
enclosure door, be sure that the jack power cord is disconnected
from the electrical outlet or other electrical power source.
Table 10 - Troubleshooting Guide
Solution
Cycle cylinder up and down several times to bleed trapped air.
Add Enerpac HF oil as required.
Have hydraulic system inspected by Enerpac authorized service center.
Repair or replace components as required.
Cycle cylinder up and down several times to bleed trapped air.
Add Enerpac HF oil as required.
Check all points where air might leak into system.
Have hydraulic reservoir and intake screen fl ushed and cleaned by
Enerpac authorized service center.
Check AC line voltage.
Use a shorter extension cord.
Use an extension cord with a thicker wire gauge.
Add Enerpac HF oil as required.
Drain reservoir and refi ll with Enerpac HF oil.
Have hydraulic system inspected by Enerpac authorized service center.
Repair or replace components as required.
Have hydraulic system inspected by Enerpac authorized service center.
Repair or replace components as required.
Have control valve inspected by Enerpac authorized service center.
Repair or replace as required.
11
DANGER: High voltage is present in the jack electrical
system even when motor is off . Before removing the
electrical enclosure cover or opening the electrical
WARNING: Always unplug jack power cord from
electrical outlet before replacing any fuses.
WARNING: All electrical troubleshooting procedures
must be performed by a trained and qualifi ed electrician.
WARNING: Never tighten or loosen hydraulic fi ttings
while jack hydraulic system is pressurized.
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