Outdoor disconnectors, produced in accordance with the Driescher
company´s documentation, used for several years on high-voltage
long-distance lines, have proven their high reliability and
safety of operation. Disconnectors are intended particularly
for terminal branchings in radial arrangement.
Disconnectors satisfy standards IEC 129, IEC 694 and
IEC 265. Using insulators satisfy the third grade of contmination area
according.
Simple load disconnectors of a sturdy structure proved
themselves in an excellent way under very different climatic
conditions.
The foundation welded frame is made of open steel profiles
which guarantee perfect surface protection from corrosion caused by heat zinc
coating that can be controlled on all places. The shafts of the load
disconnectors mounted in bronze bearings as well as all other steel components
are protected by heat zinc coating, too.
All current conduction components
are made of silver plated electrolytical copper and constitute a loopless
current conduction path.
The cross-section of the conductors on the current
conduction path is sufficiently dimensioned. Appropriate contact pressures of
the stainless steel springs ensure optimum prerequisites for faultless
switching even after several years of the load disconnector operation under
extreme operating conditions as well as under load.
The load disconnectors
are delivered with such made of a cyclo-aliphatic resin or porcelain
bearings.
The load disconnectors can be provided with earthing switches
located on the under side. The use of earthing switches requires a double or
triple drive with a sturdy blocking mechanism preventing incorrect handling.
The number of pull rods and pendulum bearings is correspondingly
increased.
Control of the load disconnectors and earthing switches is
ensured by means of hand, possibly motor outdoor drives.
The load
disconnectors can be provided with encased auxiliary switches (IP 44
protection) installed directly on the frame of the device ensuring thus
reliable switching-on and switching-off signalling.
The values of the
short-circuit resistance are kept so as to ensure an adequately large reserve.
These values apply both for the disconnectors and built-in earthing
switches.
The construction of the load disconnectors and the quality of the
materials being used ensure low cost operating conditions and
maintenance.
Under normal operating conditions it is not necessary for
the load disconnectors to undergo a preventive maintenance during the period
of ten years.
Withstand voltages of 6400 and 6410
disconnectors
|
Rated voltage |
kV |
12 |
25 |
38,5 |
| Rated short-time withstand power frequency voltage/1min.
to be applied in both dry wet environmental conditions |
|
against the earth, across the poles |
kV |
28 |
50 |
80 |
|
across the isolating distance |
kV |
32 |
60 |
90 |
| Rated lightning pulse withstand voltage |
|
against the earth, across the poles |
kV |
75 |
125 |
180 |
|
across the isolating distance |
kV |
85 |
145 |
210 |
The switching devices can further be complemented with
the following auxiliary equipment
- hand operated drives mechanisms
- motor operated drives
- auxiliary switches
- fuses (of HH type)
|
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