DOCA0095EN

Temperature

The following temperatures are relevant for circuit breakers:

  • Ambient temperature: the temperature of the air immediately surrounding the circuit breaker. If the temperature inside the enclosure is above 40 °C (104 °F), devices must be derated.

  • Operating temperature range: -25 °C to +70 °C (-13 °F to +158 °F).
    NOTE: Commissioning is possible down to -35 °C (-31 °F).

  • Storage temperature range: -50 °C to +85 °C (-58 °F to +185 °F).

The following table gives the standard circuit breaker ampere ratings depending on the frame rating and the operating temperature in the enclosure.

Temperature

 

Frame Rating In (A)

°C

°F

 

15 to 125

40

104

 

15

20

25

30

35

40

45

50

60

70

80

90

100

110

125

45

113

 

14

19

24

29

34

39

44

49

58

67

77

87

99

107

121

50

122

 

14

19

24

28

33

38

42

47

56

64

73

83

96

103

117

55

131

 

13

18

23

27

32

37

41

45

55

61

70

80

92

99

112

60

140

 

12

18

22

26

31

36

39

44

53

59

67

76

85

94

109

65

149

 

12

17

21

25

31

35

37

42

51

55

63

72

80

89

104

70

158

 

11

16

20

24

30

33

36

40

48

53

59

68

69

76

100

The following table gives the correction factor that applies to tripping time depending on ambient temperature:

Temperature

 

Frame Rating In (A)

°C

°F

 

15

20

25

30

35

40

45

50

60

70

80

90

100

110

125

10

50

 

1.21

1.16

1.15

1.16

1.13

1.14

1.17

1.16

1.16

1.18

1.19

1.19

1.21

1.19

1.17

15

59

 

1.18

1.13

1.13

1.14

1.14

1.14

1.14

1.14

1.14

1.14

1.14

1.14

1.14

1.14

1.14

20

68

 

1.15

1.11

1.11

1.11

1.09

1.10

1.12

1.11

1.11

1.13

1.12

1.12

1.15

1.13

1.12

25

77

 

1.11

1.08

1.08

1.08

1.07

1.07

1.09

1.08

1.08

1.10

1.0

1.10

1.12

1.10

1.09

30

86

 

1.08

1.06

1.05

1.06

1.05

1.05

1.06

1.06

1.06

1.06

1.06

1.06

1.09

1.07

1.06

35

95

 

1.04

1.03

1.03

1.03

1.02

1.03

1.03

1.03

1.03

1.03

1.03

1.04

1.05

1.04

1.03

40

104

 

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

45

113

 

0.96

0.97

0.97

0.97

0.98

0.97

0.97

0.97

0.97

0.96

0.96

0.99

0.99

0.98

0.96

50

122

 

0.92

0.94

0.94

0.94

0.95

0.95

0.94

0.94

0.94

0.92

0.92

0.96

0.94

0.94

55

131

 

0.87

0.91

0.91

0.91

0.93

0.92

0.90

0.91

0.91

0.88

0.88

0.89

0.92

0.90

0.90

60

140

 

0.83

0.88

0.88

0.87

0.90

0.89

0.87

0.87

0.88

0.84

0.83

0.84

0.85

0.85

0.87

65

149

 

0.78

0.85

0.85

0.84

0.87

0.86

0.83

0.84

0.84

0.79

0.79

0.80

0.80

0.80

0.83

70

158

 

0.72

0.81

0.82

0.80

0.85

0.83

0.79

0.80

0.81

0.75

0.74

0.75

0.69

0.70

0.80

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