Basic Info
Model NO.: IST-11/631
Structure: Three-column Disconnector
Operation: Manual
Movement Mode: Horizontal Rotary Type
Grounding: Single Ground
Run: Turn the Horizontal
Structure of Operating: Manual
24: Kv
Trademark: OEI Power
Origin: China Zhejiang
Type: High-voltage
Installation: Outdoor High-voltage
Grounding Mode: Grounding
Number of Poles: Three Pole
Series: Three
Common Model: Ist
Certification: IEC IEEE
12: Kv
36: Kv
Specification: IEC IEEE

These disconnectors are , no load switching devices
which physically isolate the lines. They are designed for
horizontal outdoor application and can also be designed
for vertical installation. For earthing and closing of
switchyard portions of the installation, the earthing
switches 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 61694:2112: Common Specifications for High Voltage Switchgear and Controlgear
BS 729: Hot dip galvanized coating on iron and steel articles
IEC62271-112
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 2211m above sea level, humidities of up to 91%, average ambient temperature of +31篊 with a minimum of -1篊 and a maximum of +41篊 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 61694.
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 81 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
51 Hz
Rated lightning impulse withstand voltage
211 kV
Rated power frequency withstand voltage, dry
95 kV
Rated normal current
411 Amps
Rated short time withstand current for 3 sec, min.
18.1 kA
Minimum creepage distance of insulators
911 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 temperature rise.
SUPPLIMENTARY NOTES
Suppliers should give sufficient information including drawings (which must be brief, clear and to the point) on how their switch designs addresses these requirements. Further, Suppliers may offer better alternatives that are of cost benefits to customer, It istherefore imperative that schedule "B" is completed by the tenderer. Any deviations/modifications/alternatives specification must be listed in schedule "C.
33kV 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 temperature rise.
SUPPLIMENTARY NOTES
Suppliers should give sufficient information including drawings (which must be brief, clear and to the point) on how their switch designs addresses these requirements. Further, Suppliers may offer better alternatives that are of cost benefits to custoemr.
11kV without 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 temperature rise.
SUPPLIMENTARY NOTES
Suppliers should give sufficient information including drawings (which must be brief, clear and to the point) on how their switch designs addresses these requirements. Further, Suppliers may offer better alternatives that are of cost benefits to
33kV without 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 temperature rise.
SUPPLIMENTARY NOTES
Suppliers should give sufficient information including drawings (which must be brief, clear and to the point) on how their switch designs addresses these requirements. Further, Suppliers may offer better alternatives that are of cost benefits to.