I've got a dimmer here that has instructions quoting '99 NEC 380-9(b)(2)exception.
Exception to (b): Where no grounding means exists within the snap-switch enclosure or where the wiring method does not include or provide an equipment ground, a snap switch without a grounding connection shall be permitted for replacement purposes only. A snap switch wired under the provisions of this exception and located within reach of conducting floors or other conducting surfaces shall be provided with a faceplate of nonconducting, noncombustible material.
I've got an ungrounded metal box, let's say, can I put the dimmer in, in place of the snap switch?
What confuses me is that the opening words of 380-9(b) says "Snap switches, including dimmer switches,
. . ." and the exception uses snap switches
The dimmer manufacturer implies that I can install the dimmer in an ungrounded box without adding a ground.
Oww, my head hurts. :confused