Alimak Scando 650 DOL, Technical Description

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Drive unit
A compact unit with two or three pinions engages the rack of
the mast. Each pinion is fitted to a high efficiency helical gear
box driven by a flexible coupling, by a direct start or frequency
controlled, squirrel cage induction motor with built-in electro-
magnetic disc brake.
The drive unit is connected to the car by pull rods.
The connection between car and drive unit means that the hoist
is prepared for an overload sensing system. (OSS).
The safety device is completely independent from the drive unit
and installed inside the car with two pinions engaging the rack.
The device is actuated by a centrifugal weight and stops the
hoist when the normal rated speed is exceeded.
FC vs DOL
Frequency controlled electric motors give:
– better (softer) riding comfort when starting and stopping.
– better stopping accuracy.
– less brake wear.
– hoist speed can be reduced during installation and inspection
procedures, which is not possible with direct on line (DOL)
started electric motors.
ALIMAK 34747 - 1/01
A
9
Pulse encoder
on gearbox