Reference to IEC 60-1

• maintain test voltage for 1 min.

• during wet test, if one disruptive discharge occurs on self-restoring insulation, then repeat test to pass

• test both wet and dry conditions

• atmospheric corrections, reference IEC 60-1

Reference to IEC 60-1

• maintain test voltage for 1 min.
• dry conditions only

• wet test:

• dew test:

Reference to IEC 60-1

• standard impulse: 1.2/50 m s
• dry conditions only
• 15 impulses each test condition and each polarity
• to pass:
  max. 2 discharges per series allowed on self-restoring insulation, AND no discharges on non-self-restoring insulation

OR to pass:

• 3 consecutive impulses on each polarity and condition with no discharges.
• if discharge occurs on self-restoring insulation, then 9 additional impulses with no discharges are required to pass.

Reference to IEC 694

Standard Test:

1. test voltage 10% higher than rated one minute power freq. withstand voltage
2. test voltage 10% higher than rated lightning impulse dry withstand voltage

• total of 6 impulses to each terminal: 3 positive polarity,
  3 negative polarity, with other terminal and base grounded
• to pass:
  same criteria as above
  
• flashover to ground during 3X9 series is a non-event
• only one flashover to ground is allowed per each 3X9 series
• Bias Test method (acceptable alternative) also cited for switches rated 362 kV and above

Reference to IEC 60-1

• standard impulse: 250/2500 m s

• both polarities

• wet tests for outdoor gear only

• insulation between poles, dry test conditions only

[no reference to determination of withstand values]

Reference to IEC 60-1

• When open gap withstand voltage is higher than phase-to-earth withstand voltage, different test methods are used.

combined voltage tests

• Power-frequency voltage test: two different voltage sources, in out-of-phase conditions

• Impulse voltage test: rated impulse voltage applied to one terminal; complementary voltage from another source of opposite polarity is applied to other terminal

only one voltage source

• total test voltage applied between one terminal and earth; opposite terminal is earthed

ACCEPTANCE CRITERIA:

• No acceptance specifications given in IEC 694

• two classes: Class A & Class B
• classes depend on service conditions

Two test series:

1. Table VIII of IEC 694 for rated withstand voltage to earth
1. Second Test is either of:

1. Class A

• standard impulse: 250/2500 m s

• both polarities

• both dry and wet (per IEEE 4-1978) tests required

• withstand voltage determined by "Up-and-Down Method," per C37.34 and IEEE 4-1978

• dry conditions only

• 3 applications of switching impulse voltage

• apply switching impulse withstand voltage on one terminal and apply bias voltage of 60 Hz on opposite terminal. Timing must be such that the polarity of one voltage crest is opposite from the polarity of the voltage crest on the other terminal of the switch.

ACCEPTANCE CRITERIA:

• no flashovers across open gap

OR

• if only one flashover occurs across the open gap, then 9 additional consecutive impulses are applied. One flashover to ground is permitted during the 3X9 series.

(No References or specifications cited)

Reference to IEC 1180-1

Short-duration power-frequency withstand:

• test voltage is 2000 V
• duration 1 min.
• no disruptive discharge allowed

Reference IEC 694

(No References or specifications cited)

• switch both open and closed

• only for rated voltage (U) higher than 123 kV

• apply voltage of 1.1U/Ö ` 3

• duration: 5 min.

• pass if radio interference level is less than 2500 m V

Reference IEC 694, and:

• tests subject to special agreement between user and manufacturer

• switch both open and closed
• no atmospheric corrections at present
• apply voltage at rated power-frequency of device