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The wire connectors covered by these requirements are intended for use with copper conductor in accordance with installations covered by the National Electrical Code, NFPA 70; the Canadian Electrical Code, Part I, C22.1; and NOM 001 SEDE, Standard for Electrical Installations. The requirements in this standard cover twist-on style splicing sealed wire connectors intended for installations for applications noted below:

a) In accordance with wiring methods where the connector is installed in enclosures rated for the environment and located in dry locations, damp locations, wet locations, below grade, or above grade.

b) In lighting systems operating at 30 volts or less (rated 25 amperes and 30 volts, 42.4 volts peak, maximum), and lighting equipment connected to a Class 2 power source; where the connector is located in dry locations, damp locations, wet locations, direct buried locations, below grade, or above grade where protected from direct exposure to sunlight.

NOTE: Sealed wire connectors used in these applications do not require the use of an enclosure.

c) In Canada, Class 2 circuits located in dry locations, damp locations, wet locations, direct buried locations, below grade, or above grade where protected from direct exposure to sunlight. In the United States and Mexico, Class 2 and Class 3 circuits located in dry locations, damp locations, wet locations, direct buried locations, below grade, or above grade where protected from direct exposure to sunlight.

NOTE: Sealed wire connectors used in these applications do not require the use of an enclosure. 

Splicing sealed wire connectors covered by this standard are intended for use with single or multiple conductor underground feeder cable, golf course sprinkler cable, underground low energy cable, irrigation cable, or other cable with insulation acceptable for direct burial, below grade use, or wet locations. 

Splicing sealed wire connectors covered by this standard are intended for use with copper conductor sizes 30 AWG (0.05 mm²) through 6 AWG (13.3 mm²) with currents not exceeding the ampacity of insulated conductors rated either 75 °C (167 °F) or 90 °C (194 °F) and intended for use at 600 V or less. 

For products intended for use in Canada, general requirements are given in CAN/CSA-C22.2 No. 0.