Zakład Wytwórczy Aparatów Elektrycznych Sp. z o.o.
7
2.2. Housing
The housing is made of aluminium metal sheet, grade PA4, covered by powder painting epoxy color. Doors are
stuffed with silicone seal. The construction of housing is on protection level IP55 with simultaneous ventilation
of the interior air. It has been achieved thanks by labyrinth seal of drive shaft's output on the top of housing and
using net-protected gland hole in the bottom of housing.
2.3. Driving mechanism
Driving mechanism consists:
• electric motor,
• multi-stage gearing,
• helical gear,
• gearing.
The electric motor drives a lead screw through a two-stage gearing. As a result of rotation of the screw, the
nut mounted on the screw moves along the screw causing rotation of the cooperating forks. A gear wheel is
mounted on the shaft of the fork, cooperating with the gear mounted on the driving shaft. As a result of using
a helical gear unit, the angle of rotation of the output shaft is limited to 192 °. The maximum torque is about
800 Nm.
2.4. Climatic conditions
Operating mechanisms are dedicated to outdoor switchgears in the following conditions:
a) temperature (from – 50°C to + 40°C),
b) air humidity (up to 100% at 20°C),
c) altitude (up to 1000 m),
d) wind speed (up to 30 m/s).
