Grounding data center help

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PowerdT

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What is the best practice to install grounding for the data center service racks. The situation is There is 120/208 panel, I am not sure if the panel has actual ground wire, the contractor might used the EMT as ground I need to verify that. Can I install panduit 19inch ground busbar on the racks and use #6AWG using the EMT as ground?

Thank you.
 
What would the Panduit ground bar be connected to?
What are you trying to accomplish?
Grounding for the data center racks is not an NEC issue, as long as all the equipment is connected to an EGC that runs with the supply circuit.
Is this an Art 645 data center?
 
You can do pretty much whatever you want as long as you bond the additions to the existing EGC/GES, but what do you want to accomplish? If there is an EGC, then all of the connected equipment will get that (if there's isn't any EGC, then there's a different problem).

Many people will take a #6 from a lug on each rack to some terminal point that's bonded to the existing EGC, but in general, it doesn't do anything useful (expect pay the contractor).
(Tom beat me to it :D)
 
I didn't answer this as I am not sure what you are trying to do
Can I install panduit 19inch ground busbar on the racks and use #6AWG using the EMT as ground?
Is the EMT below the raised floor and you want to jumper from the EMT to the ground bar?
Kinda like above from myself and zbang, won't do much, makes a great time and materials job
Somewhere there may be a spec for bonding the raised floor. Its not an NEC issue
 
tom baker said:
What would the Panduit ground bar be connected to?
What are you trying to accomplish?
Grounding for the data center racks is not an NEC issue, as long as all the equipment is connected to an EGC that runs with the supply circuit.
Is this an Art 645 data center?
Click to expand...
Panduit ground bar will be connected to the server racks. Customer wants EGC to be terminated to the ground busbar
 
Having and using the EGC with the supply conductors is assumed. It has to happen. You can run the EGC to a common grounding busbar. No problem there.

In a data center it can also be assumed there is a common or facility "Earth ground" system, likely already in the raised floor. Typically there may be a spec saying to connect to the Earth ground. This is an additional GEC conductor to the shared common facility Earth grounding system (typically run separately from the supply conductors and EGC, a different system).
 
Traditionally to avoid surges and electrical noise the data center is all bonded together by itself then the bonding runs back to the EGC all by itself. The theory is that switching surges and harmonics should not be seen at the data center because it is not in the return path. At that time the power supplies were linear and the majority of equipment was low noise instrumentation and communication. Since today’s data centers run on mostly switching power supplies they are the source of a lot of harmonics. The noise argument has reversed but the principle remains.

The IEER guide for sensitive electronics shows you tons of situations and grounding issues to be aware of and gives basic construction guidelines for data centers. It’s not so much what you build it with as it is to maintain short grounding paths that are loop free.
 
We typically install a ground bar in the room with a GEC run to either building steel for a steel frame building or a ground riser on an all concrete building. From there a #6 goes to all of the equipment.
 
infinity said:
We typically install a ground bar in the room with a GEC run to either building steel for a steel frame building or a ground riser on an all concrete building. From there a #6 goes to all of the equipment.
Click to expand...
Is this taken from a standard somewhere? Where does the #6 size come from?
 
When I have been ask this question I always say #6 as if a comm ( intersystem) bond. That is what I see most on prints. This is for a data rack, metal rack with equipment. Not a data processing center.
 
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