Enerpac PR-Series Electric - Handbuch (Seite 11)

11
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 flag
(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 flag 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.
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.
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
enclosure door, be sure that the jack power cord is disconnected
from the electrical outlet or other electrical power source.
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 qualified electrician.
WARNING: Never tighten or loosen hydraulic fittings
while jack hydraulic system is pressurized.
Table 10 - Troubleshooting Guide
Symptom Possible Cause Solution
1. Sporadic cylinder
action.
Air trapped in hydraulic system. Cycle cylinder up and down several times to bleed trapped air.
Low oil level in hydraulic reservoir. Add Enerpac HF oil as required.
Seal wear and/or other internal damage. Have hydraulic system inspected by Enerpac authorized service center.
Repair or replace components as required.
2. Noisy operation. Air trapped in hydraulic system. Cycle cylinder up and down several times to bleed trapped air.
Low oil level in hydraulic reservoir. Add Enerpac HF oil as required.
Air leaks in hydraulic system. Check all points where air might leak into system.
Clogged or blocked pump intake screen. Have hydraulic reservoir and intake screen flushed and cleaned by
Enerpac authorized service center.
3. Unusually slow
operation.
Low voltage. Check AC line voltage.
Extension cord too long. Use a shorter extension cord.
Extension cord wire gauge not thick
enough.
Use an extension cord with a thicker wire gauge.
4. Oil is overheating. Low oil level in hydraulic reservoir. Add Enerpac HF oil as required.
Oil viscosity too high or too low. Drain reservoir and refill with Enerpac HF oil.
High pressure leakage at the pump. Have hydraulic system inspected by Enerpac authorized service center.
Repair or replace components as required.
5. Pump runs but will not
pump oil.
OR
Cylinder moves but
will not lift load.
Seal wear and/or other internal damage. Have hydraulic system inspected by Enerpac authorized service center.
Repair or replace components as required.
Control valve needs repair. Have control valve inspected by Enerpac authorized service center.
Repair or replace as required.
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