National Electrical Installation Standards

Standards as High as Your Own

Tuesday, November 28, 2017


Re: CQD answer published Tuesday, November 21, 2017 -

Here is the answer to today's question: Excluding any specific local requirements which may have been lawfully enacted, the Colorado State Electrical Board follows the requirements of the 2017 National Electrical Code without exception.  Whether dealing with a service conductor or feeder, the rules found in 230.70 and 225.32 are quite similar. The disconnect must be located either 1) outside or 2) inside nearest the point of entrance of the conductors.  There are some widely-scattered local requirements, imposed either by local fire authorities, building departments, or power companies, where an exterior disconnect may be necessary.  As always, if in doubt, check with your local AHJ. 

J Grant Hammett



Hey J Grant thanks for your comment and checking with the AHJ before doing an installation is always better. The wording in 225.32 and 230.70 is similar but there is a significant difference. A branch circuit or feeder disconnecting means has to be nearest the point of conductor entrance whether the disconnecting means is inside or outside as stated in the second sentence of 225.32. Service disconnecting means only need to be nearest the point of conductor entrance if inside as stated in 230.70(A)(1).

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