This specification covers an ozone-resisting crosslinked rubber insulation compound for electrical wires and cables. The polymer shall consist substantially of ethylene-alkene copolymer (EAM) or ethylene-alkene diene terpolymer (EADM). This polymer type includes ethylenepropylene copolymer (EPM) and ethylenepropylene diene terpolymer (EPDM). The crosslinked insulation shall conform to the requirements for physical properties specified. Tests shall be performed in accordance to the following test methods: AC voltage withstand test; insulation resistance; DC voltage withstand tests; capacitance and dissipation factor; partial discharge level test; accelerated water absorption; and ozone resistance.

1.1 This specification covers an ozone-resisting crosslinked rubber insulation compound for electrical wires and cables. The polymer shall consist substantially of ethylene-alkene copolymer (EAM) or ethylene-alkene diene terpolymer (EADM). This polymer type includes ethylenepropylene copolymer (EPM) and ethylenepropylene diene terpolymer (EPDM).

1.2 This type of insulation is considered suitable for use on wire or cable which will be used in wet and dry locations with conductor temperatures up to 90°C during continuous operation, to 130°C during emergency overload conditions, and to 250°C during short-circuit conditions. It is considered suitable for all sizes and voltage classifications of single- and multiple-conductor power cables up to 35 000 V phase-to-phase at the 100 % insulation level and up to 25 000 V at the 133 % insulation level as listed in Table 1D, Conductor Sizes, Insulation Thicknesses, Test Voltages, and Corona Extinction Levels for Ethylene-Propylene Rubber Insulation, of Test Methods D470. Single-conductor cables shall have a supplementary covering over the insulation, and multiple-conductor cables shall have an overall covering.

1.3 Whenever two sets of values are presented, in different units, the values in the first set are the standard, while those in parentheses are for information only.

1.4 In many instances the insulation material cannot be tested unless it has been formed around a conductor or cable. Therefore, tests are done on insulated wire or cable in this specification solely to determine the relevant property of the insulation and not to test the conductor or completed cable.