Exceptions Using 'Existing' without Times

摘要

It Is Very Doubtful That The National Electrical Code(NEC) will ever adopt a definition of "existing" with a time attached, such as "existing for at least six months," or "existing for a year or more," etc. There are cases where the intent of the Code is thwarted, albeit legally, by the use of an exception that uses the word "existing." Take a single-family dwelling service pan-elboard, 100 ampere, with two mains [up to six permitted. Sec. 230.71(A)], one two-pole 40 ampere for an electric range, and one two-pole, 50 ampere feeding another panelboard for all of the other load. This panelboard is by definition a power panelboard [408.14(B)] and does not require overcurrent protection ahead of it.