raised floor grounding... NEC article #?

[in the wind]

I have been questioned about the proper grounding requirement for a computer room raised floor, Can anyone help me find the NEC article number. I searched article 545,250 and the entire index but I can't find the specific information I'm searching for. Thank You for your help.

 

[Terrynistler]

Try art 645 spec 645.15 I think that might answer your questions.

 

[bdarnell]

Check out this link : http://ecmweb.com/nec/code_qa/electric_stumped_code_37/

Scroll down the page and there is a question regarding the NEC requirements for grounding a raised floor. Specifically, there are none, however, the IT guys will always demand it. It's more for static drain than anything.

 

[gardiner]

If you contact the manufacturer of the raised floor they should be able to supply you with a detail on the most effiecent grounding method for their floor along with the requirements. Most manufacturers have had indepent labs test their floors for the optimal grounding required.

If you send me a private message with the name of the raised floor manufacturer I might have the details and related information available.

 

[dereckbc]

There are no code references for raised floor grounding, other than 250.4 that states anything likely to become energized shall be bonded... It is a design choice. It can be as simple as bonding one of the pedestals that support the grid, to as elaborate as constuction a grid of #6 AWG ro 2/0 on 2-foot centers and bonding everything under the raised floor to the grid including the cabinets installed on the raised floor.

As stated most manufacures offer details for bonding the grid. Contact the manufacture for details.

 

[roger]

I agree with the others but, if you must provide a static ground wire, here is a product I have used before.

Roger

 

[cadpoint]

I agree with the others but, if you must provide a static ground wire, here is a product I have used before.

Roger

Roger, I did research Erico for other things but I know I have used
a very similar clamp if not this one for conduits on unistruit /kendorf.
I guess the "RGC" will be the disquailier next time I run into a box of these, thanks or the insight.

 

[infinity]

I agree with the others but, if you must provide a static ground wire, here is a product I have used before.

Roger

We have used those Caddy straps in the past and they're inexpensive and excellent product since they install quickly with only one tool.

As others have said this is purely a design issue. Over the years we have had spec's that called for every fourth pedestal to be connect to a #6 copper conductor and terminating on a grounding buss or cad welded to building steel. Other clients have simply grounded one pedestal on each side of the floor. Again, it's the choice of the guy designing the system or the guy paying the bill.