Disconnectors DES, DESB

Operation Manual

Drawings — DESB and DES Disconnectors, 1000 and 630 A

A disconnector is a three-pole electrical switching device with a visible air break in the electrical circuit, designed, together with an operating mechanism, for opening and closing energized sections of a high-voltage electrical circuit with no load current, or for changing the connection scheme:

for safe work on the disconnected section;
for switching the charging currents of overhead and cable lines and transformer no-load current.

An earthing switch is a three-pole electrical switching device intended for earthing disconnected sections.
The operating mechanism is intended for manual closing and opening of disconnectors and earthing switches.
Disconnectors and earthing switches are installed in three-phase AC networks with an industrial frequency of 50 Hz and voltage ratings of 7.2 and 12 kV.

Indoor disconnectors, earthing switches and operating mechanisms are designed for operation at altitudes up to 1000 m above sea level, at ambient temperatures from +40°C to -60°C, in rooms with natural ventilation without artificially controlled climatic conditions. The room where disconnectors, earthing switches and operating mechanisms are installed must be enclosed, explosion- and fire-safe, and free from aggressive gases and vapors in concentrations that may damage insulation and protective coatings.

Technical characteristics

Rated voltage, corresponding to the highest operating voltage, kV

7.2; 12

Rated current, A

630; 1000

Rated short-time withstand current, peak value (thermal withstand current), kA

20

Highest peak value of the rated short-time withstand current (dynamic withstand current), kA

50

Disconnector versions

Depending on the arrangement of earthing blades

Version I

Earthing blades on the side of the disconnecting contacts
Version II

Earthing blades on the side of the hinge contacts
Version III

Earthing blades on both sides

Depending on the arrangement of bushings

Version I

Without bushings (DES, DE)
Version II

Bushings on the side of the hinge contacts (DESB, DES)
Version III

Bushings on the side of the disconnecting contacts (DESB, DES)

Operating mechanism versions

With red handle

For operation of disconnector earthing blades and the earthing switch
With black handle

For operation of disconnector main blades

Advantages over other manufacturers

Galvanized steel frame, eliminating paint peeling issuesl;
Option to order disconnectors with angle adjustment without welding, using an adjustable lever; adjustment step — 15°;
Convenient rod length adjustment from the operating mechanism side, not from the disconnector side;
All current-carrying elements are nickel-plated.

The following requirements were considered during disconnector design

Interchangeability

The disconnectors can be used to replace failed units in existing equipment while preserving all mounting and connection dimensions, as well as the kinematics.
Optimized dimensions

All disconnectors rated 630 and 1000 A have identical overall dimensions, and no additional interphase insulation is required.

Operation Manual

Drawings — DESB and DES Disconnectors, 1000 and 630 A