Locking Devices - Siemens 3AK Operating Instructions Manual

Fig. 25 Heater (71.)
Conditions
Disconnected position
Operating position
9229 9923 176 0B
2013-09-09
Heater (condensation water protection)
Electrical manual closing/electr. locking device
In the basic version, the vacuum circuit-breaker module with on-site connection is
closed by direct mechanical unlatching of the closing spring. Instead of this mechan-
ical manual closing, "electrical manual closing" is also available.
In this version, the closing circuit of the vacuum circuit-breaker module is electrically
actuated by a sensing device and must also be enabled via a command element
from the control room.
With on-site closing, this permits taking into account system-related interlocking and
allows you to prevent unintentional closing by the control room, for example. This
allows for interlocking the vacuum circuit-breaker module, for example, via the aux-
iliary contact of a disconnector.
Vacuum circuit-breaker modules with electrical manual closing cannot be switched
mechanically.

Locking devices

To lock vacuum circuit-breakers as a function of the switching position, the spring
charge mechanisms of the vacuum circuit-breaker can be equipped with a locking
device. This is also the case for vacuum circuit-breakers on switch gear trucks, in
withdrawable sections or with disconnectors.
The vacuum circuit-breaker must only be switched on in operating or disconnected
position. The operating or disconnected position is the position of the vacuum circuit-
breaker on the switchgear truck or withdrawable section in the switchgear. At the
same time, the vacuum circuit-breaker may be moved on the switchgear truck or
withdrawable section only when it is open.
Positions of the vacuum circuit-breaker in the switchgear
The isolating distance between the vacuum circuit-breaker contacts and the switch-
gear counter-contacts is attained fully .
The vacuum circuit-breaker is inserted fully into the switchgear and the vacuum cir-
cuit-breaker contacts overlap completely with the switchgear counter-contacts.
The heater limits condensation and corrosion of the vac-
uum circuit-breaker module.
To this end, the heater has to be connected to the sup-
ply voltage (see circuit diagram included with the deliv-
ery).
The heater's surface temperature is at the most 180 °C.
Power consumption 50 W
Description
25