Class ANSI

Main 
Demension
in (mm)

leak-
age
Dist-
ance in (mm)

Com-
bined 
M & E Stre-
ngth b(KN)

Mceb
anical Impact Strenth in-1b(N-m)

Time Load 
Test Value
1b (KN)

Average 
Flashover Voltage

Power Freq-
uaency Punc-
ture Voltage KV

Radio influence Voltage

D(max)

F

Power Frequ-
ency

Critcal 
Impulse

Test
Volt-
age
To
Gro-
und
KV

Max Riv At 1MHz V

Dry kv

Wet kv

Positive kv

Nag-
ative
kv

52-1

61/2
(165)

51/2
(141)

7(178)

10000
(44)

45(5.0)

6000
(27)

60

30

100

100

80

7.5

50

52-2

8
(203)

53/4
(146)

81/4
(210)

15000
(67)

50(5.5)

10000
(44)

65

35

115

115

90

7.5

50

52-3

103/4
(273)

53/4
(146)

111/2
(292)

15000
(67)

5.5(6.0)

10000
(44)

80

50

125

130

110

10

50

52-4

103/4
(273)

53/4
(146)

111/2
(292)

15000
(67)

5.5(6.0)

10000
(44)

80

50

125

130

110

10

50

52-5

103/4
(273)

53/4
(146)

11
(279)

25000
(111)

60(7.0)

15000
(67)

80

50

125

130

110

10

50

52-6

103/4
(273)

53/4
(146)

11
(279)

25000
(111)

60(7.0)

15000
(67)

80

50

125

130

110

10

50

52-9

41/2
(114)

61/4
(160)

63/4
(171)

10000
(44)

45(5.0)

6000
(27)

80

30

100

90

80

7.5

50