What codes/standards apply to a wall switch. 1

[bvanhiel]

I'm a mechanical engineer designing the physical enclosure for a product that will be installed and wired similarly to a standard 110V wall switch. This product will eventually be sold to the US market.

What is the best way to find the applicable codes? I'm mostly concerned with the physical dimensions (to mount in a standard switch box), and required material properties of the enclosure material (to identify the plastic that meets the constriants). There is obviously some UL testing, but what else?

 

[davidbeach]

Read the applicable portions of the National Electrical Code (NEC) (NFPA-70). Switches, boxes, and box fill will be of particular interest, others might also depending on the application.

 

[bvanhiel]

Wow. UL 20 seems to be the standard I need. It's $700 for the pdf . Can anyone summarize the physical dimensions for me?

 

[davidbeach]

You need to bite the bullet and buy the codes and standards you need.

 

[bvanhiel]

We're at an early prototype stage. $700 for the UL standard can't be justified. Already have a copy of the NEC, first pass didn't yield much, so I'll be taking a closer look at it.

 

[stevenal]

The NEC deals with the installation of listed devices, not the construction of the devices. There is a UL forum here. I suspect your size limits will be similar to the maximum sizes of other devices meant for the boxes, such as GFCI receptacles and dimmers.

 

[gepman]

I believe what you are referring to is call a "snap switch" in UL terminology and UL 20 is indeed the standard. UL standards are usually only purchased by a manufacturer or someone very interested in how the product is tested. End users can usually get enough information regarding the product and application from the UL "General Information Directory" which is available for free online at

http://www.ul.com/regulators/2006WhiteBook.pdf

I recommend this book for everyone that applies UL equipment.

I recommend that you buy UL 20 but if you don't you should just buy a couple of snap switches and flush device boxes and reverse engineer the dimensions from them.

Order from McMaster-Carr or someone like them.

 

[mcgyvr]

If you are a current customer of UL you get any standard for free now.
They started that maybe 1 year ago.

and if you can't justify 700 bucks for 1 standard you might as well just quit now...

 

[bvanhiel]

As gepman pointed out... I can measure some dimmer switches for free. None of them exceeded 35mm. All the info I needed for right now, and not worth $700 to find that I can go to 35.2mm.

 

[stevenal]

Who?