0611CT1603

Environmental Conditions

Ambient Temperature

PowerPact B-frame circuit breakers may be used between -25°C (-13°F) and +70°C (158°F).

For temperatures higher than 40°C (104°F) inside the enclosure, devices must be derated.

Circuit breakers should be put into service under normal ambient, operating temperature conditions.

Exceptionally, the circuit breaker may be put into service when the ambient temperature is between -35°C (-31°F) and -25°C (-13°F).

The permissible storage-temperature range for PowerPact B-frame circuit breakers in the original packing is -50°C (-67°F) and +85°C (185°F).

Altitude Derating

Altitude does not significantly affect the characteristics of PowerPact B-frame circuit breakers up to 2000 m (6560 ft). Above this altitude, it is necessary to take into account the decrease in the dielectric strength and cooling capacity of air.

The following table gives the corrections to be applied for altitudes above 2000 m (6560 ft).

The breaking capacities remain unchanged.

Altitude

2000 m
(6560 ft)

3000 m
(9840 ft)

4000 m
(13120 ft)

5000 m
(16400 ft)

Impulse withstand voltage (kV)

8

7.1

6.4

5.6

Insulation voltage (V)

Ui

800

710

635

560

Maximum operational voltage (V)

Ue

690

690

635

560

Average current capacity (A) at 40°C (104°F)

In x

1.0

0.98

0.96

0.94

Vibrations

PowerPact B-frame devices resist mechanical vibrations.

They meet following levels of IEC 60068-2-6:

  • 2.0 to 25 Hz and amplitude ±1.6 mm.

  • 25 to 100 Hz acceleration ±4 g.

Excessive vibration may cause tripping, breaks in connections or damage to mechanical parts.

   
   

Climatic Withstand

The materials used in PowerPact B-frame circuit breakers will not support the growth of fungus and mold.

PowerPact B-frame circuit breakers have passed the test defined below for extreme atmospheric conditions.

Dry cold and dry heat:

  • IEC 60068-2-1-dry cold at -55°C.

  • IEC 60068-2-2-dry heat at +85°C.

Damp heat (tropicalization):

  • IEC 60068-2-30–damp heat (temperature + 55°C and relative humidity of 95%).

  • IEC 60068-2-52 severity 2 - Cycling salt mist.

Electromagnetic Disturbances

PowerPact B-frame circuit breakers have successfully passed the electromagnetic compatibility tests (EMC) defined by the following international standards: IEC/EN 60947-2: Low-voltage switchgear and controlgear, part 2: circuit breakers.

PowerPact B-frame circuit breakers are protected against:

  • Overvoltages caused by circuit switching.

  • Overvoltages caused by an atmospheric disturbances or by a distribution-system outage (such as from failure due to lightning).

  • Devices emitting radio waves (radios, walkie-talkies, radar, etc.).

  • Electrostatic discharges produced directly by users.

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