Dimmer switches

[Wendell Swedberg]

ICC test question:

Dimmer switches installed in a nonmetallic box with a plastic cover utilizing plastic cover retntion screws rquire which of the following?

A) Conductors suitable for 105 degrees celsius
B) Effective grounding and a means provided for grounding metal faceplates.
C) Integral metal plates with fins for heat dissipation
D) No device or cover grounding is required.

The answer is A...

I've done word searches in the ocde book and I can find any reference to get me to the answer A? Does anyone know why "A" is the answer and the code reference?

thanks,
Wen

[Brandon Chew]

Wen,

I would choose answer B and use the following for my reference:



§RE3901.11 Snap switch faceplates. Snap switches mounted in boxes shall have faceplates installed so as to completely cover the opening and seat against the finished surface.

§RE3901.11.1 Faceplate grounding. Snap switches, including dimmer and similar control switches, shall be effectively grounded and shall provide a means to ground metal faceplates, whether or not a metal faceplate is installed. Snap switches shall be considered effectively grounded where either of the following conditions are met:

1. The switch is mounted with metal screws to a metal box or to a nonmetallic box with integral means for grounding devices.

2. An equipment grounding conductor or equipment bonding jumper is connected to an equipment grounding termination of the snap switch.

I underlined the part that applies to the question.

Brandon

[Scott Patterson]

I'm sure it has to do with the fact that a dimmer switch produces heat. That would make "A" the most logical choice.

[Brandon Chew]

I agree that dimmers produce heat, but "105 degrees celsius" is hot, hot, HOT! :eek:

That temp would likely burn a child's fingers on contact.