Schneider Electric Class 615 dimensions Longer Service, Life of Electrical Installations

Suitability for Isolation (Positive Contact Indication)

Compact® NSF and NSJ 150 to 600 A Circuit Breakers

Section 2—General Characteristics

The limiting capacity of a circuit breaker is its ability to limit short-circuit currents.

06153040	Isc
	Prospective
	Isc Peak

Prospective

Current

Prospective

Isc

Limited

Isc Peak

Actual

Current

Limited

Isc

tsc t

	The exceptional limiting capacity of the Compact® NS line is due to the double break technique (rapid
	natural repulsion of contacts and the appearance of two arc voltages in series with a steep wavefront).
	The limiting capacity of the Compact NS line greatly reduces the forces created by fault currents in
	devices. The result is a major increase in breaking performance. In particular, the service breaking
	capacity Ics is equal to 100% of Icu.
	The Ics value, defined by IEC 947-2, is guaranteed by tests comprising the following operations:
	• Breaking a fault current equal to 100% of Icu three times consecutively
	• Checking that the device continues to function normally
	• Conduction of rated current without abnormal temperature rise
	• Protection functions perform within the limits specified by the standard
	• Suitability for isolation is not impaired
Longer Service	Current limiting circuit breakers greatly reduce the negative effects of short circuits on installations.
Life of Electrical
Installations
Thermal Effects	Less temperature rise in conductors, therefore longer service life for cables.
Mechanical Effects	Reduced electrodynamic forces, therefore less risk of electrical contacts or busbars being distorted or
	broken.
Electromagnetic	Less disturbance for measuring devices located near electrical circuits.
Effects

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