Environmental Conditions

Ambient Temperature

The ambient temperature refers to the temperature of the air immediately surrounding the circuit breaker.

Operation temperature
- –25 to +70 °C (–13 to +158 °F): Normal operating temperature
  
  NOTE: The minimum operating temperature for the earth-leakage fault indicator on the MicroLogic 4 and 7 trip unit is -15 °C (5°F). Between -15 and -5 °C (5 and 23 °F), and when operating the device with an earth leakage fault and a very low load compared to the trip unit rating In, the earth leakage indicator may not work correctly (fault indication or reset).
- –35 to –25 °C (–31 to –13 °F): Commissioning possible

Storage temperature
- –50 to +85 °C (–58 to +185 °F): Without MicroLogic trip unit
- –40 to +85 °C (–40 to +185 °F): With liquid crystal MicroLogic trip unit or PowerTag Energy

Extreme Atmospheric Conditions

ComPact NSX circuit breakers are designed to operate in industrial atmospheres as defined in standard IEC/EN 60947-2 for the highest level of pollution (level 3).

They are tested for extreme storage conditions according to 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 –55 °C (–67 °F)
IEC/EN 60068-2-30	Damp heat, cyclic temperature +55 °C (+131 °F) relative humidity 95 %
IEC/EN 60068-2-52	Salt-mist test

To obtain the best use from the circuit breakers, install them in properly ventilated switchboards where excessive dust is not a problem.

Vibration

ComPact NSX circuit breakers are tested against vibration.

Conformity tests are carried out in accordance with standard IEC/EN 60068-2-6 at the levels of severity required by the merchant shipping regulatory bodies (IACS, Veritas, Lloyd namely):

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

Electromagnetic Disturbances

ComPact NSX circuit breakers are immune to electromagnetic disturbance.

They comply with the requirements of the electromagnetic compatibility (EMC) standard:

Standard	Title
IEC/EN 60947-2 appendixes F and J	Overcurrent protection tests
IEC/EN 60947-2 appendixes B and J	Specific tests for earth-leakage protection

Check for compliance with EMC standards by testing for immunity to:

Overvoltages produced by the operation of electromagnetic switchgear.
Overvoltages produced by atmospheric disturbance that pass through the electrical network (for example, lightning).
The use of apparatus emitting radio waves (such as radio transmitters, walkie-talkies, or radar).
Electrostatic discharges produced by the operators themselves.

Conformity with EMC standards as described above helps to ensure that:

The circuit breaker operates correctly in a disturbed environment:
- Without nuisance tripping.
- In accordance with the trip time.
There is no disturbance to any type of industrial or commercial environment.

Altitude

ComPact NSX circuit breakers are designed to operate within specification at altitudes of up to 2,000 m (6,600 ft).

Above 2,000 m (6,600 ft) modifying the characteristics of the surrounding air (dielectric strength, cooling capacity) causes derating as follows:

Altitude (m/ft)	< 2,000 m (6,600 ft)	3,000 m (9,800 ft)	4,000 m (13,000 ft)	5,000 m (16,500 ft)
Maximum operating voltage (V)	690	590	520	460
Maximum operating voltage (V) for NSX400K	1000	886	790	696
Rated thermal current (A) at 40 °C (104 °F)	In	0.96 x In	0.93 x In	0.9 x In

Altitude (m/ft)

< 2,000 m

(6,600 ft)

3,000 m

(9,800 ft)

4,000 m

(13,000 ft)

5,000 m

(16,500 ft)

Maximum operating voltage (V)

690

590

520

460

Maximum operating voltage (V) for NSX400K

1000

886

790

696

Rated thermal current (A) at 40 °C (104 °F)

0.96 x In

0.93 x In

0.9 x In