Interrupteur aé Rien à Commande Manuelle Rocking Disconnectors

Center Break Isolator and double Break Isolator
These disconnectors are , no load switching deviceswhich physically isolate the lines. They are designed forhorizontal outdoor application and can also be designedfor vertical installation. For earthing and closing ofswitchyard portions of the installation, the earthingswitches are provided on disconnector. If required.The following documents were referred to during the preparation of this specification. In case of conflict, the provisions of this specification shall take precedence.
IEC 129:1975: Alternating Current Disconnectors (Isolators) and Earthing Switches
IEC 60694:2002: Common Specifications for High Voltage Switchgear and Controlgear
BS 729: Hot dip galvanized coating on iron and steel articles
IEC62271-102
Isolator (Disconnector) - a mechanical switching device which provides, in the open position, an isolating distance in accordance with Electrical Safety requirements.SERVICE CONDITIONS
The isolator shall be suitable for continuous operation outdoors in tropical areas at altitudes of up to 2200m above sea level, humidities of up to 90%, average ambient temperature of +30ºC with a minimum of -1ºC and a maximum of +40ºC and heavy saline conditions along the coast.4.2. DESIGN AND CONSTRUCTION
4.2.1 The Isolator, Solid link shall be designed and constructed in accordance with IEC 129 and IEC 60694.
4.2.2 The isolating link shall be of the vertical opening, designed for single phase manual operation. It shall be easily removed and replaced by using a portable operating rod.
4.2.3 The isolating link shall incorporate double porcelain insulators to suit voltage requirements and mounted on hot dipped galvanised steel under base suitable for vertical mounting.
4.2.4 The isolating link shall be arranged so that each unit is mounted independently on an angle bracket. It shall be supplied complete with the angle bracket and accessories suitable for mounting on 'U' type steel channel. The drawings to be submitted shall indicate all the applicable mounting positions.
4.2.5 The isolator shall be designed such that in fully open position, it shall provide adequate electrical isolation between the contacts on each phase. It shall conform to the requirement as single point isolation for safety.
4.2.6 All steel parts shall be hot dip galvanized to BS 729. The minimum coating of galvanizing required is 80 microns.
4.2.7 The solid link shall be removable from the mounting by use of operating rod.
4.2.8 All current carrying parts of the isolator shall be made of high conductivity material.
4.2.9 The isolator shall be fitted with clamp connectors for Aluminium (ACSR) conductor ofAluminium (ACSR)conductor of up to 18.2mm diameter.The rating of the complete isolator shall be as follows: -
Rated voltage
36 kV
Rated frequency
50 Hz
Rated lightning impulse withstand voltage
200 kV
Rated power frequency withstand voltage, dry
95 kV
Rated normal current
400 Amps
Rated short time withstand current for 3 sec, min.
18.0 kA
Minimum creepage distance of insulators
900 mmSystem Voltages132kV1System:50 Hz, 3phase2Neutral Point EarthingSolidly EarthedEarthing Resistor3Nominal voltage of networks132kV4Highest system voltage as defined by IEC - 38145kV5Short circuit not less than [MVA] N/A6Short circuit and earth fault current, symmetrical r.m.s. value not less thanN/A7Thermal short circuit current, 1 second not less than31.5 kA8Dynamic Peak current not less than80 kA9Continuously rated currents of Isolating Switches:1 600 A10Isolation Voltage according to IEC - 7110 a- Switching Surge withstand voltage Phase to earth 275 kV- Longitudinal impulse component of combined test325 kV10 b- Lightning Impulse withstand voltage 1.2/50 micro-s To earth and between phases650kVpAcross the isolating distance of isolating switches750 kVp10 c- Test voltage at power frequency 1 minute, dry and wet
(at sea level)To earth and between phases (r.m.s.)N/AAcross the isolating distance of isolating switchesN/A11For the design and erection of the conductors in the switchyard the following minimum distance shall be observed:11aPhasetoground [mm]1 500 11b- Phasetophase2 33011cBusbars phasetophase3 50011dHeight to live parts above ground5 50011eHeight to live parts above ground at
service/transportation strips [mm]5 50011f- Lowest part of insulators above ground [mm]3 50012Maximum temperature rise of conductors
above ambient temperature (45oC)40oC13Maximum wind pressure on conductors and cylindrical objects430N/m214Maximum wind pressure on flat surfaces820N/m215Minimum nominal creepage distance as defined in IEC 815, Table II25 mm/kV