click on above pictures to view enlarge view !
The Surge Arrestors are an indispensable protection devise which needs to protect a transformer against natural lightning & switching surges in a high voltage system. They are designed for satisfactory performance in critical atmospheric conditions of high/low temperatures & humidity. Asiatic offers the latest Gap less Metal oxide technology which is far superior than conventional systems being used previously in terms of vast improvement in VA curves & increased through current capability at over voltages.

Features

  • The heart centre of the Surge Arrestor is a highly non-linear Zinc oxide discs also called Varistor capable of withstanding the surges.
  • Housed in non-porous Porcelain or Silicone rubber housing along with other circuitry duly sealed.
  • During passage of an electrical surges, the zinc discs allows the entire energy to earth by posing a very low resistance & instantaneously recovers to its original insulation property after passage of surge , getting ready for the next operation.
  • Robust sturdy design in Porcelain housing with top Aluminium casted cap & bottom copper cap which totally seals the mechanism inside.
  • The Surge Arrestor in Silicone rubber is comparatively light weight & UN-breakable, hydro phobic, resistant to UV rays, chemicals, ozone & corona. Further it offers excellent resistance to ageing under climatic conditions, electrical stresses & exhibits non-combustible properties.
  • Can withstand rough handling or shipping. Reduced weight offers easy transportation.
  • Both Porcelain & Silicone rubber arrestors can be supplied with mounting brackets.
  • The flexible, thin sheds in Silicone rubber makes it possible to achieve highest creep age distances in comparatively shorter housing. In an unlikely event of a failure of a Surge arrestor due to excessive surges, porcelain housing may crack or burst in all directions but silicone rubber insulator may merely split open thereby preventing vandalism and damage to the adjacent equipments.
  • The optional disconnecter can also be supplied which helps to disconnect ground lead from arrestor to avoid supply interruption & violent shattering of arrestor..

MOV DISCS

The Surge arrestor has been extensively type tested at Central Power Research Institute- a laboratory of International repute as per IEC 60099 – 4 for all test including pollution (tracking & corrosion) test as per IEC 61109 for 1000 hrs…

  Type Designation
GMOSA-P/GMOSA-S
  Discharge class
Distribution class
  Rated voltage, kV
9/12
  Maximum continuous operating voltage, kV
7.65/10.2
  Ref. current at amb. Temperature
1mA
  Ref. voltage at amb. Temperature
9/12
  Nominal discharge current, kA
5/10
  Steep current impulse residual voltage, kV
9
  Standard referred
IEC60099-4
  Lightning Impulse residual voltage (in kV at 8/20 µs current impulse
9
  Partial discharge in pico coulomb – pC
less than 5 pC
  High current impulse with stand at 4/10 µs
65 kA/100 kA
  Lightning Impulse protection level, kV
75
  Material of arresters terminals
Stainless steel
  Conductor size suitable for line terminals, mm²
25-95
  Ambient air température range,ºC
-5 to +55
  Type of the disconnecting device
Optional disconnector provided
  Method of mounting
Optional Bracket Provided
  test
test2