computer grounding grid

[Loderunner]

should a computer floor grounding grid be attached to the building steel .

 

[ron]

Re: computer grounding grid

It must be connected to the facility grounding electrode system, which would include building steel.

 

[Physis 2]

Re: computer grounding grid

I'm not gonna disagree that it should be, but, just for fun , must it be connected to the grounding electrode system?

 

[petersonra]

Re: computer grounding grid

what is so special about this piece of metal that it can't be connected to a common egc by code?

there may be other reasons to do so, but I don't see that the NEC requires it.

 

[Physis 2]

Re: computer grounding grid

I don't see where it's "required".

It's not listed in 250.50

Edit: to add emphesis.

[ October 28, 2005, 03:45 PM: Message edited by: Physis 2 ]

 

[dereckbc]

Re: computer grounding grid

Originally posted by Loderunner:
should a computer floor grounding grid be attached to the building steel .

Yes, in addition every piece of conduit, pipe, raceway, floor pedestals, rebar it is near too. And that is just the end points. It should also be bonded to every SDS serving the area, all AC panel ground buses, and the GES. Then from the grid to every equipment cabinet in the area.

 

[ron]

Re: computer grounding grid

My point was, that eventually everything is connected to the grounding electrode system.

 

[hurk27]

Re: computer grounding grid

By Dereck: Yes, in addition every piece of conduit, pipe, raceway, floor pedestals, rebar it is near too. And that is just the end points. It should also be bonded to every SDS serving the area, all AC panel ground buses, and the GES. Then from the grid to every equipment cabinet in the area.

Now Dereck I thought you were against multi-point grounding?

Wouldn't it be better to single point everything back to the system grounding buss?

 

[dereckbc]

Re: computer grounding grid

Originally posted by hurk27:
Now Dereck I thought you were against multi-point grounding?

Wouldn't it be better to single point everything back to the system grounding buss?

Depends on the application. Single point isolated is only for special apps where manufactures require it. In most cases it is for telephone switching equipment made by Lucent, Nortel, etc.

Funny thing the new soft switches comming out now use a "Mesh" technique which is very much like a grid on steroids, or in the cases like Cisco they want thier equipment installed on a sheet of copper or some other conductive metal to form a equipotential ground plane. It is getting crazy.
What is stranger is Cisco use the grounding/bonding paths as a return for load currents along with return conductors. Have not quite figured out how they get it UL certified.

 

[hurk27]

Re: computer grounding grid

By Dereck What is stranger is Cisco use the grounding/bonding paths as a return for load currents along with return conductors. Have not quite figured out how they get it UL certified.

WoW
I wounder how they keep their 0 reference signal clean?
That is insane