I recently was asked to review a series of emails from a colleague about equipment requirements for ready access or, as defined in Article 100 and used within text in the National Electrical Code (NEC), as “readily accessible.” This phrase is used to describe the location of circuit breakers, for example, permitting ready access to turn the circuit off during times of emergency, when something malfunctions, or when working on the circuit or the electrical equipment in a de-energized condition, as normally required by NFPA 70E. The definition of “readily accessible” was changed in the 2014 NEC and may have highlighted an issue, prompting the string of emails from the electrical equipment’s manufacturer and the installation’s electrical inspector.
The NEC’s definition of readily accessible states: “capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to actions such as to use tools, to climb over or remove obstacles, or to resort to portable ladders and so forth.” The underlined text is new for the 2014 NEC but not new for anyone working on or installing electrical equipment, because the requirement for “no tool access” for certain equipment installations has long been a rule that everyone understood, even if the “no tool rule” wasn’t previously in the definition.
The first use of “readily accessible” in the 2014 NEC is in 90.2(C), where the authority having jurisdiction (AHJ) may grant an exception for installation of conductors and equipment, not under the exclusive control of the electric utilities, to connect to the electric utility supply system as long as these conductors are outside of the building or structure or these conductors terminate to the utility company conductors inside the building at a readily accessible location nearest the point where the utility conductors enter the building or structure. This text uses “readily accessible” without regard to the use of tools but just requires the connection to be readily accessible without having to use portable ladders or similar methods to gain access to the connections.
One of the most common applications for “readily accessible” occurs in 240.24(A), in which the NEC states that overcurrent devices must 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 6 feet, 7 inches above the floor or working platform. However, the readily accessible requirement does not apply to all overcurrent devices. There are four exceptions to this rule:
- For busways
- For supplementary overcurrent protection in accordance with 240.10
- For overcurrent devices in accordance with 225.40 where the feeder devices are not readily accessible if the branch-circuit devices are readily accessible and the same for service overcurrent devices are not readily accessible where the feeder or branch-circuit overcurrent devices are readily accessible
- For overcurrent devices adjacent to utilization equipment that these devices protect, access is permitted to be by portable means (such as in 404.8(A), Exception 2, with the disconnect switch permitted at the height of the equipment where the height exceeds the 6 foot, 7 inch handle height)
In 240.10, if the overcurrent device is supplementary protection, such as internal protection for some types of electrical equipment, it is not required to be readily accessible. Supplementary protection can be installed inside lighting poles to provide individual protection for luminaires and can be protection for internal control components and for electrical components in appliances or similar equipment. The supplementary devices can be located behind bolted enclosure doors, in boxes, and inside other bolted electrical equipment. A circuit breaker or a set of fuses can be located inside of an enclosure with a bolted cover where the handle of the breaker or the handle of the fusible switch is readily accessible.
Another example of an overcurrent device located inside of an enclosure is where a transfer switch has integral overcurrent protection built into the transfer switch. If the transfer switch is designed for manual load transfer, the transfer switch is designed with an external switch handle so it can be operated with the door in the closed and latched position; otherwise, if the door must be in the open position to operate the switch, the transfer switch is not listed for manual operation with the door in an open, unlatched condition, only in an unloaded and de-energized condition.
Check the design, listing and the NEC for any electrical equipment employing internal overcurrent protection to determine whether a bolted cover and nonaccessibility of the overcurrent device is acceptable.