Liebherr EP 944 C Stationary Material Handler - Manual (Page 7)

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7 EP 934 C EP 944 C EP 954 C Material Handlers
Reliability
Backed by more than 30 years experience in the construction of electrically pow-
ered excavators, Liebherr designed the new EP 934 C, EP 944 C and EP 954 C
with the aim of providing top performance whatever the challenge might be. The
structure of the excavator, using components from our own manufacture for the
electric drive, has been completely rethought, and so moves away from simply
being an adaptation of the diesel-engine excavator.
Being intended for key functions in the organization of industrial sites, Liebherr
electric Material Handlers provide a very high level of reliability. The service life
of the hydraulic components has also been increased thanks to the smoother
movement of the electric drive.
The concept of the single actuator (one single electric motor for all the hydraulic
functions) allows for the risk area associated with the low voltage at the electric
cabinet to be reduced even further.
Electrical
system Totally integrated into the structure of the uppercarriages
and accommodated in a metal container, the electric cabi-
net provides a three-fold level of protection to the compo-
nents of the electrical system:
- Mechanical (insulation from vibrations and from the pos-
sible impact of falling objects)
- Heat (maintains a constant temperature thanks to the
heating resistors which prevent corrosion from conden-
sation)
- Electrical earthing of the structure and disconnection
from current is controlled from the cab by way of a mo-
torised circuit-breaker.
Protected electric
cabinet The electric cabinet, like the rotating joint, provides IP55
class protection. A double fi ltration system (accessible
from the outside) places the cabinet under pressure,
which avoids any dust penetration and, with permanent
ventilation, ensures the thermal balance of all the com-
ponents.
Electric motor Liebherr electric excavators are equipped with motors
especially designed for really tough applications. The di-
mensions of the motor allow for the full power to be drawn
from the kinematic chain, and so maximises the perform-
ance of the machine. The motor can resist a momentary
overload of up to +25 % of its rated capacities.
Protected against penetration by water and dust, its prop-
erties correspond to protection class IP55.
The temperature of the roller bearings and other bearing
elements is constantly monitored, and, in the event of
overheating, the operator is warned of malfunction on the
console at the driving position.
Cooling system
• Generous dimensions for high
cooling capacity
• Vertical arrangement for in-
creased effi ciency and minimal
incursion of foreign bodies
• Powered by a thermostatically
regulated hydraulic motor
• Hinged to allow for complete
cleaning
• Reversible actuation of the fan
(without time limit) as option
Elastic base
• Complete range of elastic bases especially
designed for each model
• Absorption of mechanical stresses (normally
transferred to the chassis of an excavator) if
mounted on a rigid structure (anchored metal
body, concrete body)
• Protection for the machine (in particular the
elements of the rotation assembly), as well as
for the load-bearing structure, against the axial
and radial forces generated by the operating
dynamics
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