Preface
This is the first edition of CSA C22.2 No. 268, Power circuit breakers up to 1000 Vac/1500 Vd, one of a series of Standards issued by CSA Group under Part II of the Canadian Electrical Code.
When published, this Standard will replace CSA TIL D-34.
For general information on the Standards of the Canadian Electrical Code, Part II, see the Preface of CAN/CSA-C22.2 No. 0, General Requirements – Canadian Electrical Code, Part II.
Certain material in this Standard has been taken from IEEE C37.20.1-2002, Metal Enclosed Low-Voltage Power Circuit Breaker Switchgear. Reprinted with permission from IEEE, 3 Park Avenue, New York, New York, 10016-5997 USA, Copyright 2002, by IEEE.
Scope
1.1
This Standard applies to power circuit breakers rated 1000 Vac or less nominal, 1058 Vac (RMS) maximum, and 1500 V dc maximum for use in nonhazardous locations in accordance with the Canadian Electrical Code, Part I.
1.2
This Standard applies to power circuit breakers of the following types:
a) stationary (fixed) mounted or drawout mounted types;
b) manually operated or power operated;
c) with or without electromechanical or solid-state type trip devices;
d) unfused power circuit breakers;
e) power circuit breakers with integrally mounted current limiting fuses;
f) power circuit breakers intended to be connected in series with current limiting fuses in a drawout assembly to form a non integrally fused circuit breaker; and
g) of two-, three-, or four-pole construction.
1.3
The circuit breakers covered by this Standard are intended for installation in circuit breaker enclosures, switchboards, switchgear, motor control centres, and similar equipment. The acceptability of the combination of a circuit breaker with respect to any overall enclosure will be determined by evaluation of the complete product assembly.
1.4
This Standard covers the requirements for direct acting current and voltage protective functions of
a) direct-acting overcurrent electromechanical trip devices;
b) direct-acting overcurrent electronic trip systems; and
c) undervoltage trip devices
1.5
This Standard does not apply to moulded case and insulated case circuit breakers covered by CSA C22.2 No. 5.
1.6
In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the Standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.