Fill in the blanks with the correct answers. New requirements for marking of cable trays apply when the cable trays installed within substations contain conductors _________. The warning notice shall be installed in a conspicuous position along the cable tray at intervals not to exceed ____ ft.
- with 600V insulation; 20
- cable tray rated; 50
- rated higher than 600V; 10
- rated higher than 35kV; 20
A new section has been added to Art. 225 of the 2011 NEC. Section 225.70 outlines the warning sign requirements in substations. The term "substation" is also a new definition in Art. 100.
As noted in 225.70(A)(1)(c), a "DANGER — HIGH VOLTAGE" sign shall be placed "on all cable trays containing high-voltage conductors with the maximum spacing of warning notices not to exceed 10 ft." ANSI Z-535.2 or ANSI Z-535.4 may also provide guidelines for the warning notice.
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