33 Kv Switch Disconnectors Gang Insulator

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 +30º C with a minimum of -1º C and a maximum of +40º C 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 of Aluminium (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 mm

SOLID LINKS 11KV

TRI-LINKS

Lot 3-(a) 11kV with interrupters

FURTHER REQUIREMENTS:

Water shall not be able to accumulate on any part of the equipment nor shall any feature introduce moisture into any component.
The design shall incorporate all reasonable precautions and provisions for the safety of personnel concerned with the operation and maintenance of the same.
The current path shall be such that load current shall only flow through high conductive materials such as copper and its alloys. Load current shall not be permitted to flow through ferrous components, springs, or spring-loaded mechanisms.
All load current paths shall be so designed that the relevant parts of the switch are capable of carrying the specified rated current without exceeding the permitted tempe