NEMA AB 1
Withdrawn
A Withdrawn Standard is one, which is removed from sale, and its unique number can no longer be used. The Standard can be withdrawn and not replaced, or it can be withdrawn and replaced by a Standard with a different number.
Molded-Case Circuit Breakers, Molded Case Switches, and Circuit-Breaker Enclosures
23-07-2013
27-10-2004
Scope
Purpose
1 References, definitions, abbreviations and symbols
References
Definitions
Abbreviations and symbols
2 General
Characteristics of molded case circuit breakers
and molded case switches
3 Construction requirements
General
Corrosion protection
Operating mechanism
Spacings
Wire connectors
4 Performance requirements and verification tests
General
Standard design verification tests
Rated short-circuit current tests
5 Periodic verification tests
6 Field tests
7 Specific application circuit breakers
General
Instantaneous trip circuit breakers
Integrally fused circuit breakers
Current limiting circuit breakers
Marine circuit breakers
Mining circuit breakers
Molded case switches
Electronic trip unit circuit breakers
Switching duty circuit breakers
Circuit breakers having a short-time withstand
current rating
8 Accessories
General
General requirements
Shunt-trip release
Undervoltage trip release
Auxiliary and alarm switches
Electrical operator
Fuse accessory package
Mechanical interlock
Handle lock
9 Circuit breaker and molded case switch enclosures
Enclosures for general use
Test enclosures
10 Marking requirements
Circuit breaker marking(s)
Molded case switch marking(s)
Accessory marking(s)
Marking of enclosures
Marking information
11 Determination of short-circuit current, power
factor, and recovery voltage
Instrumentation
Circuit conditions
Alternating current circuits of 10,000 Amperes or
less
Alternating current circuits of greater than
10,000 Amperes
Recovery voltage
Direct current calibration
12 Clearances and creepage distances for circuit
breakers
Appendix
A Determination of short-circuit currents in low-
voltage systems
Three-phase systems
Single-phase, 3-wire, 120/240-volt systems
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