240.24 Location in or on Premises.
Code Change Summary: Location and accessibility requirements for overcurrent devices were clarified.
In past editions of the NEC®, “overcurrent devices” were required to be readily accessible. In the 2014 NEC®, the definition of readily accessible in Article 100 was revised to make it clear that something is not readily accessible if a tool is needed to gain access to it.
There are many types of control panels and switch enclosures that require a tool in order to gain access to the fuses inside. By changing the 2014 NEC® definition of readily accessible to mention tools, a code violation of 240.24(A) was created for certain overcurrent device enclosures that require a tool for access.
In the 2017 NEC®, the rule in 240.24(A) has been clarified. Now, switches containing fuses and circuit breakers must be readily accessible. Requiring the actual switch to be readily accessible instead of the fuse inside, means that a fuse inside a switch enclosure that requires tools to open is no longer a code violation.
The new exception states that the use of a tool shall be permitted to access overcurrent devices located within listed industrial control panels or similar enclosures.
Below is a preview of Article 240. See the actual NEC® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2017 NEC® edition of NFPA 70.
2014 Code Language:
240.24 Location in or on Premises.
(A) Accessibility. Overcurrent devices shall be readily accessible and shall be installed so that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than 2.0 m (6 ft. 7 in.) above the floor or working platform, unless one of the following applies:
(1) For busways, as provided in 368.17(C).
(2) For supplementary overcurrent protection, as described in 240.10.
(3) For overcurrent devices, as described in 225.40 and 230.92.
(4) For overcurrent devices adjacent to utilization equipment that they supply, access shall be permitted to be by portable means.
2017 Code Language:
240.24 Location in or on Premises.
(A) Accessibility. Switches containing fuses and circuit breakers shall be readily accessible and installed so that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than 2.0 m (6 ft. 7 in.) above the floor or working platform, unless one of the following applies:
(1) For busways, as provided in 368.17(C).
(2) For supplementary overcurrent protection, as described in 240.10.
(3) For overcurrent devices, as described in 225.40 and 230.92.
(4) For overcurrent devices adjacent to utilization equipment that they supply, access shall be permitted to be by portable means.
Exception: The use of a tool shall be permitted to access overcurrent devices located within listed industrial control panels or similar enclosures.