EMG ELDROclassic Ed 121/12, Руководство по сборке

Страница: 40 / 74

4 Function description
4.2 Electrical equipment
40 / 74 EMG-MA-Ed23-Ed630-V2_EN_T.Nr.344029.docx
4.2 Electrical equipment
An asynchronous alternating current motor (certain special models
also use direct current motors). The power is supplied through screw
terminals that are arranged in a terminal box. A cable inlet M25 x 1.5
is arranged on the terminal box for a wire diameter of 10 mm to 19
mm.
4.3 Function description
The hydraulics pump powered by the motor transports the hydraulics
medium to the space underneath the piston. In the process, hydraulic
pressure is generated that works toward the outside through the pis-
tons and the lifting rod.
The reversing motion of the piston and lifting rod after the motor is
switched off is realised either by a force working toward the outside
(brake weight, brake spring) or by the installed return spring. The use-
ful lifting force for the user of the ELDRO
®
device thus always repre-
sents the difference between the generated hydraulic force and the
existing external or internal counter-force.
The lifting and lowering times depend both on the load as well as the
viscosity of the hydraulics medium, which in turn is influenced by the
ambient and operating temperature. In the models with lifting, lower-
ing valve or lifting and lowering valve, the manipulating/reset speeds
of the lifting rod and thereby also the lifting and lowering times can be
adjusted steplessly.
If the piston is in the end position (e.g. in continuous operation S1),
the power input to the motor will reduce due to hydraulic principles.
This way, an overload of the ELDRO
®
device is precluded and a ther-
mal protective circuit is therefore not required.