Journeyman Electrician Exam (NEC)Special Occupancies, Equipment, and ConditionsMedium
A temporary carnival ride is being installed in a public park. The main overcurrent protective devices for the temporary installation are located in an enclosure accessible to the public. According to NEC Article 590, what is the minimum height, from the ground or operating surface, at which the operating handles of these devices must be located?
- A1.5 m (5 ft)
- B1.8 m (6 ft)
- C1.2 m (4 ft)
- D2.1 m (7 ft)
Show answer & explanationAnswer & explanation
Correct answer: B. 1.8 m (6 ft)
NEC Section 590.7(B) requires that where overcurrent protective devices are accessible to the public, their operating handles shall be not less than 1.8 m (6 ft) above the ground or operating surface. This prevents unauthorized access and tampering.
Why the other options are wrong
- A. This height is below the minimum required for public-accessible overcurrent devices in temporary installations.
- C. This height is insufficient to prevent casual public access and tampering with overcurrent devices.
- D. While safer, this height is not the minimum specified by the NEC; 1.8m (6ft) is the correct minimum.
Temporary Installation OCPD Height
The minimum vertical distance from the ground or operating surface to the operating handles of overcurrent protective devices in temporary installations when accessible to the public.
- Applies to temporary installations (NEC 590).
- Prevents public tampering with OCPDs.
- Mandated at 1.8 m (6 ft) minimum.
Memory trick: Six feet high keeps the public eye off the temporary power's control.