What's Wrong Here?

Oct 12, 2007 11:00 AM, By Joe Tedesco, NEC Columnist

Hint: Think Too-Tall Jones

”This 240V, 3-phase, 3-wire panelboard features 2- and 3-pole breakers,” says Ray Larsen, a professional engineer with PacifiCurrent Electrical Engineering in La Crescenta, Calif. “Since the breakers are not used as switches, is this a legal installation (besides having a missing cover)? The remaining breakers in use serve the building's HVAC units. The other enclosure to the right is also a 240V, 3-phase, 3-wire panel. One breaker feeds a 240V receptacle.”

This installation violates several NEC rules.

As per 240.24(A), “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 368.12.
“(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.”

In addition, 404.8 states, “All switches and circuit breakers used as switches shall be located so that they may be operated from a readily accessible place. They shall be installed such 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.” There are three exceptions to this rule, but none apply in this particular installation.

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