Preparation Of The Supporting Structure; Installation Of The Disconnector; Adjustment Of The Hand Operating, Mechanism Type He; K-Mechanism - ABB NAL Series Mounting And Operation Manual

Fig. 2 Switch-disconnector type NAL/VR with K-mechanism

4.2. Preparation of the supporting structure

The disconnectors are intended for vertical or horizontal operations.
The design of a supporting structure shall consider the geometrical
configuration of the disconnector/vertical or horizontal/and minimal
clearances to both earthed and live parts. The supporting structure
shall be rigid enough to avoid some deformation of the disconnec-
tor base. All the touching points of the supporting structure and the
disconnector base shall lay in the same plane. For construction of
the supporting structure it is recommended to use some U-iron or
angle iron components. The disconnector shall be fixed by means
of four M12 bolts arranged according to the dimensional drawing.

4.3. Installation of the disconnector

In the course of installation of the disconnector particular attention
should be paid not to deform the base of the disconnector, other-
wise some defects will occur such as the following:
In the course of installation of the disconnector particular attention
should be paid not to deform the base of the disconnector, other-
wise some defects will occur such as the following:
1. excessive rise of the starting moment of a force on the discon-
nector shaft,
2. non-simultaneity of the contacts which should not exceed 3
mm in normal conditions,
3. deterioration of contacts touch in the closed opposition,
4. displacement of the symmetry plane of moving contacts in rela-
tion to the pole symmetry plane what results in asymmetrical
touching of the fixed and moving contacts. In addition, the
operating lever will hit the lock.
To avoid these defects coming from deformations of the sup-
porting structure it is recommended to tighten initially
three bolts only when fixing the base. Some additional washers
shall be placed under the fourth bolts to prevent deformations of
the switch base when tightening the fourth bolt.
.
Fig. 3 Switch-disconnector type NAL/VR with A-mechanism
During installation be careful and do not apply too big torque on
the insulators.
Caution!
If the apparatus will work under conditions which allow the water
deposition or condensation on apparatus parts or on elements
(busbars) directly connected to it, the apparatus should not be
installed vertically with hollow insulators at the bottom. In addition,
the apparatus should be protected against the water dripping or
runoff on its insulating parts. This situation may cause a dielectric
strength deterioration of apparatus.

5.0 Adjustment of the hand operating, mechanism type HE

5.1 K-mechanism. Fig.2
Closing
Pull out arrester ring S from the front shaft of the HE-mechanism,
see Fig. 8. Turn the operating handle clockwise until the switch will
be closed and arrester ring will be latched.
Opening
Pull out arrester ring S and turn the handle counter-clockwise until
the switch will be open. After opening operation, check if the
arrester ring S work properly.
5.2 A-mechanism. Fig. 3
Closing
Pull out arrester rings S on the front shaft of the hand operating
mechanism, see Fig. 8. Turn the operating handle anti-clockwise
until the opening spring will be charged and latched. After that
operation, arrester ring should be latched. Pull out arrester ring
one more time and turn the operating handle clockwise until the
switch will be closed. Check if the arrester ring S works properly.
NAL/NALF/VR – Mounting and operation manual 5