Draft Details

1.1 These requirements cover individually enclosed air switches, rated 6000 A or less at 1000 V ac or 1500 V dc or less, having all current-carrying parts enclosed, manually operable by means of external handles, and intended to be employed in accordance with CSA C22.1, Canadian Electrical Code, Part I / NOM-001-SEDE, Electrical installations (utility) / NFPA 70®, National Electrical Code® (NEC®).

NOTE: NFPA 70®, National Electrical Code®, and NEC® are registered trademarks of the National Fire Protection Association, Quincy, MA.

1.2 As used in this Standard, the term switch is intended to mean an enclosed switch or deadfront switch unless specifically stated otherwise.

1.3 These requirements also cover dead front switches that have all current-carrying parts enclosed when mounted in an enclosed panelboard, dead front switchboard, or the like. These switches are manually operable by means of external handles and are intended to be employed in accordance with CSA C22.1, Canadian Electrical Code, Part I / NOM-001-SEDE, Electrical installations (utility) / NFPA 70®, National Electrical Code® (NEC®).

1.4 These requirements cover enclosed switches with or without provision for fuses suitable for use as branch circuit, feeder, and service overcurrent protection.

1.5 The following fuses are deemed suitable for use as branch circuit, feeder, and service overcurrent protection:

a) Cartridge Fuses;

b) Plug Fuses; and

c) Special Purposes Fuses marked as meeting the performance specifications of a specific Class Fuse.

1.6 These requirements cover enclosed switches intended for general use and having ampere ratings, with or without horsepower or kilowatt ratings, and enclosed switches intended for motor-circuit use only and having horsepower or kilowatt ratings but no general-use ampere ratings.

1.7 These requirements cover double-throw switches intended for use in optional standby systems (see CSA C22.1, Canadian Electrical Code, Part I / NOM-001-SEDE, Electrical installations (utility) / NFPA 70®, National Electrical Code® (NEC®)).

1.8 These requirements cover fused electrically tripped switches rated over 600 A and rated 600 A or less employing Class J, R or T fuses.

1.9 These requirements also cover electrically tripped switches that have been evaluated to determine their acceptability for ground-fault protection when combined with ground-fault sensing and relaying equipment as follows:

a) Switches for use with Class I ground-fault sensing and relaying equipment include those that are capable of interrupting 12 times their rated current or that have integral means to prevent disconnecting as levels of fault current exceeding the contact interrupting capability of the switch.; or

b) Switches for use with Class II ground-fault sensing and relaying equipment are capable of interrupting 10 times their rated current and are for use in ground-fault protection systems in which means to prevent disconnecting at levels of fault current exceeding the contact interrupting capability of the switch are incorporated within the ground-fault sensing and relaying equipment when combined with Class I and II ground-fault sensing and relaying equipment.

1.9A These requirements cover electrically tripped switches that have been evaluated to determine their acceptability as a ground-fault circuit-interrupter in accordance with CSA C22.2 No. 144.1 / NMX-J-520-ANCE / UL 943 or special purpose ground-fault circuit-interrupter in accordance with UL 943C. 

1.9B This Standard contains Annexes with requirements to cover the following:

a) Enclosed and Deadfront Switches Intended for Marine Use, Annex SA;

b) Open Type Switches, Annex BB; and

c) Electrical Operators, Annex CC.

1.10 These requirements do not cover:

a) Common forms of snap switches,;

b) Switches having features intended primarily for the starting and protection of motors, including the switches arranged to shunt out fuses during the starting of motors,;

c) Switches provided with automatic trips for opening them and constructed to afford overload protection without other circuit breakers or fuses,;

d) Devices in which the pulling of fuses or the removal of a detachable pullout member is designed to accomplish a switching operation;

e) Circuit breakers, molded-case switches, magnetic-only circuit interrupters, instantaneous-only circuit breakers, and supplementary protectors.; or

f) Double-throw switches for bidirectional applications.