Measurement of Resistance

 

MAIN CIRCUIT

  • current between 50 A and rated
    normal current

    AUXILIARY CIRCUIT
  • current: 10 mA

voltage: 6 V dc

  • resistance not to exceed 50 W

Measurement of Resistance

Reference to IEC 694

 

measurements only applicable for disconnectors

Measurement of Resistance

(No references or specific tests are cited)

 

Mechanical Terminal Load

  • 25 open/close cycles with rated mechanical terminal loads

After test: verifications

  1. Manual equipment - values of forces do not differ by more than 20%
  2. Electrically operated equipment - power consumed by motor during operation is not materially increased

Mechanical Terminal Loading

[1 kV < U]

  • no terminal loadings required for indoor switches
  • outdoor switches must be loading under 4 different conditions
  • 10% of rated number of operations must have mechanical loading of the terminals

 

 

Operation Under Ice

  • only if manufacturer claims suitability of equipment for ice conditions
  • clear or rime ice
  • two classes of thickness:
    10 mm and 20 mm
  • single poles can be tested only if each pole has separate operating mechanism
  • if common operating mechanism, then must test 3-pole except for rated voltages exceeding 72.5 kV
  • test both opening and closing operations
  • external surfaces free of oil & grease traces

 

ACCEPTANCE CRITERIA:

  • no reference to "chopping action" or number of attempts

  • Manual switch can be operated manually without damage affecting mechanical or electrical performance

 

  • Power-operated switch can be operated by operating device without damage affecting mechanical or electrical performance

Ice Loading Test

  • laboratory or natural environment
  • test must be under clear ice
  • ice thickness: at rated ice-breaking ability

 

 

 

 

 

 


 

  • both opening and closing operations
  • external surfaces free of oil & grease traces


ACCEPTANCE CRITERIA:

  • chopping action is acceptable means of loosening the ice for opening or closing of manual switches
  • power-operated switches must operate successfully on the first opening attempt. Multiple attempts for closing are permitted.
  • no significant change in contact forces or resistances before and after test

Operation at Temperature Limits

(No references or specific tests are cited)

Operation at Temperature Limits

10 operating cycles at each:

  • minimum ambient air temp
  • maximum ambient air temp

Operation at Temperature Limits

(No references or specific tests are cited)

Contact Zone Test

(No references or specific tests are cited)

Contact Zone Test

  • see Figures 1 and 2
  • Test to prove satisfactory operation of disconnectors in various positions of the fixed contact. Device shall open and close correctly in each position.

Contact Zone Test

(No references or specific tests are cited)

Mechanical Endurance Test

 

(No references or specifications cited)

Mechanical Endurance Test

 

  • 1,000 operations without mechanical terminal loads

 

  • If a switch operator is used, the control voltage / pressure of operator shall be:


at rated value for 900 operations
at minimum value for 50 operations
at maximum value for 50 operations

  • during tests, lubrication is allowed, but no adjustments



ACCEPTANCE CRITERIA:

  • for a dependent manual operating mechanism, operating torque shall not increase by more than 20% from the values before the test

 

  • during test must verify that control & auxiliary contacts and position-indicating devices operate satisfactorily

 

Mechanical Operations Test

 

  • rated number of mechanical operations

 

  • For power or stored energy operated switches, the control voltage / pressure / force shall be:

 

at rated value for 90% of operations

at minimum for 5% of operations

at maximum for 5% of operations

 

  • during tests, no maintenance, repairs or replacements are allowed

 

ACCEPTANCE CRITERIA:

  • contact forces or resistances before and after have no significant change

 

  • no undue wear