Peak Withstand Current Test

 

  • new device with clean contacts

 

  • three-phase or two adjacent phases


 

  • rated duration, or not less than 0.3 sec














    Short-Time Withstand Current Test
  • new device with clean contacts

 

  • three-phase or two adjacent phases

 

  • rated duration

 

AFTER TESTS, switch must:

  • exhibit no mechanical damage

 

  • carry continuous rated current without exceeding temp-rise limits

 

  • withstand rated voltage

 

  • be capable of its rated switching duties

 

  • if resistance increased by more than 20%, and contacts cannot be visually inspected, then additional temp rise test may be appropriate

Peak Withstand Current Test
Reference IEC 694

 

  • three-phase or two adjacent phases

 

  • return conductor parallel to blade and at same elevation

 

  • length of return conductor at least equal to distance. between input and output terminals of the disconnector

 

[U £ 52 kV]

  • see test arrangement (Fig. 4) for distances between input terminals and supports

 

[52 kV < U]

  • see test arrangements (Figs. 5 and 6) for connections by flexible and rigid conductors

    Short-Time Withstand Current Test

 

  • Reference IEC 694

 

  • additional notes same as above

Peak Withstand Current Test [1 kV < U]


  • three-phase or two adjacent phases

 

  • return conductor parallel to blade and at same elevation
  • conductors must be unsupported for at least the open gap distance

 

  • minimum duration: 10 cycles (0.167 sec)
  • at any convenient voltage







    Short-Time Withstand Current Test
  • new device

 

  • three-phase or two adjacent phases

 

  • minimum duration: 3 sec

AFTER TESTS, the device must:

  • exhibit no visible damage
  • withstand at least 15 open-close cycles

    If there are slight contact markings, then device must:

 

  • carry continuous rated current without exceeding allowable temperature rise

 

  • be capable of its rated switching duties

Temperature-Rise Tests

 

 

  • stabilized when temp rise does not exceed 1 K/hour

 
  • ambient air temp between 10° C and 40° C

 

  • resistance before and after temp rise test shall not differ by more than 20%

 

  • new device with clean contacts

 

  • air movement less than .5 m/s

Temperature-Rise Tests

Reference IEC 694

 

  • temp rise of main circuit is only applicable for disconnectors

Continuous Current Tests
[1 kV < U]

 

  • stabilized when 3 consecutive values of temp rise, at 30-min. intervals, show max. variation of 1 degree

 

  • ambient air temp between 10° C and 40° C

 

  • (no reference to before and after resistance)

 
  • mount device in a room substantially free from drafts

 

  • conductors at least four feet long

 

Switch Performance Test

 

  • design test - not used to establish overload rating

 

  • 180% of rated current
  • ambient air temperature between 25° C and 30° C
  • duration: 8 hours
  • temps considered stable if rise does not exceed 3% during last 4 hours of test
  • pass test if device is suitable for operation at maximum speeds without cumulative mechanical damage