Environmental Conditions
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:
-
Circuit breaker: -25 °C to +70 °C (-13 °F to +158 °F).
NOTE: Commissioning is possible down to -35 °C (-31 °F). -
Earth-leakage circuit breaker: -25 °C to +70 °C (-13 °F to +158 °F).
NOTE: The earth-leakage trip indication may not work below -15 °C (5 °F).
-
-
Storage temperature range (in original packing): -50 °C to +85 °C (-58 °F to +185 °F).
Temperature Derating for Earth-Leakage Circuit Breaker
Above the reference temperature of 40 °C (104 °F), the ampere ratings for the earth-leakage circuit breaker are given in the following derating table:
|
Circuit breaker rating In (A) |
Temperature |
||||||
|---|---|---|---|---|---|---|---|
|
40 °C |
45 °C |
50 °C |
55 °C |
60 °C |
65 °C |
70 °C |
|
|
25 |
25 |
25 |
25 |
25 |
25 |
25 |
25 |
|
50 |
50 |
50 |
50 |
50 |
50 |
50 |
50 |
|
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
|
160 |
160 |
155 |
150 |
145 |
140 |
135 |
130 |
Temperature Derating for Thermal-Magnetic (TM-D) Circuit Breaker
Above the reference temperature of 40 °C (104 °F), the ampere ratings for the circuit breaker are given in the following derating table:
|
Circuit breaker rating In (A) |
Temperature |
||||||
|---|---|---|---|---|---|---|---|
|
40 °C |
45 °C |
50 °C |
55 °C |
60 °C |
65 °C |
70 °C |
|
|
16 |
16 |
16 |
15 |
15 |
14 |
14 |
13 |
|
25 |
25 |
24 |
24 |
23 |
23 |
22 |
21 |
|
32 |
32 |
31 |
30 |
30 |
29 |
28 |
27 |
|
40 |
40 |
39 |
38 |
37 |
36 |
34 |
33 |
|
50 |
50 |
49 |
48 |
46 |
45 |
44 |
42 |
|
63 |
63 |
61 |
60 |
58 |
56 |
54 |
53 |
|
80 |
80 |
77 |
73 |
70 |
67 |
64 |
60 |
|
100 |
100 |
96 |
94 |
90 |
87 |
83 |
80 |
|
125 |
125 |
120 |
117 |
113 |
109 |
104 |
100 |
|
160 |
160 |
155 |
149 |
144 |
139 |
133 |
126 |
Correction Factor for Thermal-Magnetic (TM-D) Circuit Breaker Tripping Time
The overload protection is calibrated at 40 °C (104 °F) in the lab. This means that when the ambient temperature is below or above 40 °C (104 °F), the Ir protection pickup is slightly different.
The following table gives the correction factor that applies to tripping time depending on ambient temperature:
| Rating In (A) | Temperature | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 10 °C (50 °F) | 15 °C (59 °F) | 20 °C (68 °F) | 25 °C (77 °F) | 30 °C (86 °F) | 35 °C (95 °F) | 40 °C (104 °F) | 45 °C (113 °F) | 50 °C (122 °F) | 55 °C (131 °F) | 60 °C (140 °F) | 65 °C (149 °F) | 70 °C (158 °F) | |
|
16 |
1.16 |
1.13 |
1.11 |
1.08 |
1.05 |
1.03 |
1.00 |
0.97 |
0.94 |
0.91 |
0.88 |
0.85 |
0.81 |
|
25 |
1.13 |
1.11 |
1.09 |
1.07 |
1.05 |
1.02 |
1.00 |
0.98 |
0.95 |
0.93 |
0.90 |
0.88 |
0.85 |
|
32 |
1.14 |
1.11 |
1.09 |
1.07 |
1.05 |
1.02 |
1.00 |
0.98 |
0.95 |
0.93 |
0.90 |
0.87 |
0.84 |
|
40 |
1.15 |
1.12 |
1.10 |
1.08 |
1.05 |
1.03 |
1.00 |
0.97 |
0.95 |
0.92 |
0.89 |
0.86 |
0.83 |
|
50 |
1.13 |
1.11 |
1.09 |
1.07 |
1.05 |
1.02 |
1.00 |
0.98 |
0.95 |
0.93 |
0.90 |
0.87 |
0.85 |
|
63 |
1.14 |
1.12 |
1.10 |
1.07 |
1.05 |
1.02 |
1.00 |
0.97 |
0.95 |
0.92 |
0.89 |
0.86 |
0.83 |
|
80 |
1.21 |
1.18 |
1.14 |
1.11 |
1.07 |
1.04 |
1.00 |
0.96 |
0.92 |
0.88 |
0.83 |
0.80 |
0.75 |
|
100 |
1.18 |
1.16 |
1.12 |
1.10 |
1.06 |
1.04 |
1.00 |
0.96 |
0.94 |
0.90 |
0.87 |
0.83 |
0.80 |
|
125 |
1.17 |
1.14 |
1.11 |
1.08 |
1.06 |
1.03 |
1.00 |
0.96 |
0.93 |
0.90 |
0.87 |
0.84 |
0.80 |
|
160 |
1.17 |
1.15 |
1.12 |
1.09 |
1.06 |
1.03 |
1.00 |
0.97 |
0.93 |
0.90 |
0.87 |
0.83 |
0.79 |
Extreme Atmospheric Conditions
Circuit breakers and earth-leakage circuit breakers are designed to operate in industrial atmospheres as defined in standard IEC/EN 60947-2 and IEC/EN 60664-1 for the highest level of pollution (level 3).
Switch-disconnectors are designed to operate in industrial atmospheres as defined in standard IEC/EN 60947-3 and IEC/EN 60664-1 for the highest level of pollution (level 3).
Circuit breakers are tested for extreme storage conditions and are compliant with the following standards:
|
Standard |
Title |
|---|---|
|
IEC/EN 60068-2-2 |
Dry heat, severity level +85 °C (+185 °F) |
|
IEC/EN 60068-2-1 |
Dry cold, severity level –50 °C (–58 °F) (circuit breaker only) |
|
IEC/EN 60068-2-30 |
Damp heat:
|
|
IEC/EN 60068-2-52 |
Salt-mist, severity 2 |
To maximize lifetime, install circuit breakers in properly ventilated equipment with minimal dust.
Vibration
Circuit breakers are designed to withstand vibration. They meet the IEC/EN 60068-2-6 standard for vibration:
-
2 Hz to 13.2 Hz with an amplitude of +/- 1 mm (+/- 0.04 in.)
-
13.2 Hz to 100 Hz at a constant acceleration of +/- 0.7 g
Conformity tests are carried out in accordance with the IEC/EN 60068-2-6 standard, at the levels of severity required by the merchant shipping regulatory bodies (mainly IACS, Veritas, and Lloyds).
Excessive vibration can cause tripping, breaks in connections, or damage to mechanical parts.
Electromagnetic Disturbance
Circuit breakers resist electromagnetic disturbance. They comply with the requirements of the electromagnetic compatibility (EMC) standard IEC/EN 60947-2.
Altitude
Circuit breakers are designed to operate within specification at altitudes up to 2,000 m (6,600 ft.). Above 2,000 m (6,600 ft), the following derating is required:
|
Characteristic |
Altitude (m/ft) |
||||
|---|---|---|---|---|---|
|
2,000 m |
3,000 m |
4,000 m |
5,000 m |
||
|
Impulse withstand voltage |
Uimp |
8 kV |
7.1 kV |
6.4 kV |
5.6 kV |
|
Insulation voltage for circuit breaker |
Ui |
800 V |
710 V |
635 V |
560 V |
|
Insulation voltage for earth-leakage circuit breaker |
Ui |
500 V |
445 V |
400 V |
350 V |
|
Maximum operational voltage for circuit breaker |
Ue |
690 V |
690 V |
635 V |
560 V |
|
Maximum operational voltage for earth-leakage circuit breaker |
Ue |
440 V |
440 V |
400 V |
350 V |
|
Average current capacity (A) at 40 °C (104 °F) |
In x |
1 |
0.98 |
0.96 |
0.94 |