33kv Isolator Current 2000A Without Earth Switch

  MV Outdoor Off-Load Isolator Switch(Alternating current disconnector)  TECHNICAL  SPECIFICATIONScopeType IST off-load switchs are suitable for use in tropical zone, with a maximum ambient temperature of approximately 40 degrees Centigrade and an average temperature of approximately 28 degrees Centigrade with high humidity and heavy rainfall. The preferred operational altitude is up to 1800 m above sea level. Electrical SystemType IST off-load isolator switch are designed for continuous operation on a 3-phase 3-wire 11, 15,22,24,27and 33,36kV,50/60Hz distribution system with the star-point of the source-point transformer earthed through an Arc Suppression Coil or Earthing Resistor. Standards Type IST off-load isolator switch are complied with relevant requirements of the following standards together with all current amendments; IEC62271-102:2003 :High-voltage alternating-current disconnectors and earthing switches      IEC60129:1984    :Alternating current disconnectors and earth switches      IEC 60265-1:1998  :High voltage switches - Part 1:Switches for rated                       voltage above 1kV and less than 52kV       IEC 60694: 1996   :Common specifications for high-voltage switchgear and                       controlgear standards       IEC 60815:1986    :Guide for the selection of insulators in respect of                        polluted conditions       BS EN ISO 1461     :Hot dip galvanized coatings on fabricated iron and                                steel articles- Specifications and test methods 4.0                     Construction 4.1                     General 4.1.1                Type IST off-load isolator switchs  are the vertical/Horizontal  mounting Type for mounting on a single or H-pole structure for overhead lines or feeders from the energized sections.           4.1.2                Type IST off-load isolator switchs are compatible and ready for installation on tubular steel poles and spun concrete poles.  4.1.3    The design are of an air insulated "rocking insulator" type with two fixed insulator posts and one moving insulator post per phase.          4.1.4     All steel and iron parts shall be galvanized to protect from corrosion as per BS EN ISO 1461               4.1.5    Type IST off-load isolator switchs are  equipped with a single operating mechanism and suitable coupling bars that shall operate all phases simultaneously and that independent operations of each                        pole,irrespective of the state of the other poles,is not permitted SPECIFICATIONS i.                    Rated Voltage     12kV    24KV      36KV ii.                  Rated Continuous Current Carrying    Capacity       Not Less Than 400A Up to 630A iii.                Rated Short-Time Withstand Current (rms)    12KV      24KV    36KV          >=20KA / 3 sec    >=25KA/ 3 seciv.                 Lightning Impulse WithstandVoltage (peak)-To earth and between poles                       min                       max    12KV        24KV      36KV      60KV     75KV        95KV     125KV       145KV      170KV   -Across the isolating distance   min                           max        70KV     85KV    110KV     145KV     165KV      195KV v.                   Power Frequency Withstand Voltage(r.m.s)     -To earth and between poles     12KV     24KV        36KV      28KV       50KV        70KV    -Across the isolating distance     32KV     60KV       80KVvi.                 Average Ambient Temperature    (Maximum)             28ºC(40ºC) i.                    Humidity Range             0-100%ii.                  Preferred Altitude Requirement          Up to 1,800miii.                InsulatorsTotal Creepage Distance (mm)                       Min                      Max     12KV      24KV     36KV     192      384     576     465        600     9001.1                           Operation 1.1.1                Type IST off-load isolator switchs are designed to provide a smooth, Lightweight action requiring minimum maintenance.   1.1.2                The complete operating mechanism parts are sufficiently Insolated from live parts, and grounded for the safety of the operator. The operating mechanism shall be of robust,adjustable design with padlock facility in either the "OPEN" and "CLOSE" positions.   1.1.3                The complete operating mechanism are comed complete with an Operating handle and shall be designed for steady manual operation From ground level.   1.1.4                The insulation for the operating mechanism handle are sufficient For the safety of the operations and preferably incorporated with an Anti-slip grip.   1.1.5                The vertical drive rod is  suitable length and shall be provided With facilities to extend or reduce the length. Suitable couplings and operating rod guides shall be supplied with each operating mechanism.       1.1.6                 If  possible, it can be designed that the operating mechanism handle use for both LEFT and RIGHT hand operations. The dire