Bonding of data racks - Electrician Talk - Professional Electrical Contractors Forum
CLICK HERE AND JOIN OUR COMMUNITY TODAY, IT'S FREE!
Go Back   Electrician Talk - Professional Electrical Contractors Forum > Electrical Trade Topics > Structured Wiring


Like Tree11Likes
  • 5 Post By CoolWill
  • 2 Post By splatz
  • 1 Post By wcord
  • 1 Post By Navyguy
  • 1 Post By wcord
  • 1 Post By Incognito
Reply
 
Thread Tools Display Modes
Old 05-21-2019, 12:58 PM   #1
Beam Me Up Scotty
 
Kevin_Essiambre's Avatar
 
Join Date: Feb 2017
Location: Ottawa, Ontario, Canada
Posts: 651
Rewards Points: 142
Default Bonding of data racks

Hey Everyone,

I've been thinking about the bonding of data racks for rack mount equipment, as I have bid on a job in a residential building that will have a rack.

I've installed a couple of rack mount pieces before, and they have a screw on the back for "grounding" to the rack, even though it had a power cord with a ground/bonding pin (standard 5-15 plug).

Should I be bonding the rack mount system to the ground in the panel? My understanding with this, is that it can cause parallel bonding/grounding paths? I can't wrap my head around how to avoid that without not bonding the rack.

For residential is it even required?

Any input would be of help.
__________________
"If the women don't find you handsome, they should at least find you handy!"
Kevin_Essiambre is offline   Reply With Quote
Join Contractor Talk

Join the #1 Electrician Forum Today - It's Totally Free!

ElectricianTalk.com - Are you a Professional Electrical Contractor? If so we invite you to join our community and see what it has to offer. Our site is specifically designed for you and it's the leading place for electricians to meet online. No homeowners asking DIY questions. Just fellow tradesmen who enjoy talking about their business, their trade, and anything else that comes up. No matter what your specialty is you'll find that ElectricianTalk.com is a great community to join. Best of all it's totally free!

Join ElectricianTalk.com - Click Here JOIN FOR FREE


Warning: The topics covered on this site include activities in which there exists the potential for serious injury or death. ElectricianTalk.com DOES NOT guarantee the accuracy or completeness of any information contained on this site. Always use proper safety precaution and reference reliable outside sources before attempting any construction or remodeling task!

Sponsored Links
Advertisement
 
Old 05-21-2019, 01:11 PM   #2
Senior Member
 
CoolWill's Avatar
 
Join Date: Jan 2019
Location: SC
Posts: 1,867
Rewards Points: 2,012
Default

I believe they should be bonded. And what does it matter if there is parallel grounding/bonding?
__________________
I'm With Her! Hillary 2016
CoolWill is offline   Reply With Quote
Old 05-21-2019, 01:44 PM   #3
Beam Me Up Scotty
 
Kevin_Essiambre's Avatar
 
Join Date: Feb 2017
Location: Ottawa, Ontario, Canada
Posts: 651
Rewards Points: 142
Default

Quote:
Originally Posted by CoolWill View Post
I believe they should be bonded. And what does it matter if there is parallel grounding/bonding?
Ontario Electrical Code says to abandon a ground if there are parallel paths, hence my worries.

Sent from my Samsung using Tapatalk
__________________
"If the women don't find you handsome, they should at least find you handy!"
Kevin_Essiambre is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 05-21-2019, 02:30 PM   #4
Senior Member
 
CoolWill's Avatar
 
Join Date: Jan 2019
Location: SC
Posts: 1,867
Rewards Points: 2,012
Default

Quote:
Originally Posted by Kevin_Essiambre View Post
Ontario Electrical Code says to abandon a ground if there are parallel paths, hence my worries.

Sent from my Samsung using Tapatalk
Does that mean parallel earth grounds, or parallel bonding paths? I could understand earth grounds being problematic, but bonding paths are often in parallel. Metal conduit, building steel, multiple circuits in a box, etc.
__________________
I'm With Her! Hillary 2016
CoolWill is offline   Reply With Quote
The Following 2 Users Say Thank You to CoolWill For This Useful Post:
Kevin_Essiambre (05-21-2019), TGGT (05-21-2019)
Old 05-21-2019, 05:11 PM   #5
Beam Me Up Scotty
 
Kevin_Essiambre's Avatar
 
Join Date: Feb 2017
Location: Ottawa, Ontario, Canada
Posts: 651
Rewards Points: 142
Default

Quote:
Originally Posted by CoolWill View Post
Does that mean parallel earth grounds, or parallel bonding paths? I could understand earth grounds being problematic, but bonding paths are often in parallel. Metal conduit, building steel, multiple circuits in a box, etc.
I know grounds and bonds are not the same, however, if there's a shorter bond connection (say 3 feet) through the power cord with a 14 AWG ground, wouldn't the stray voltage try to take the 14 AWG before the longer 6 AWG? This is the reason why we had abandoned the bonding conductors in 14 AWG teck cable from a generator with a 3 AWG ground. If a short was caused, there's the risk of the 14 AWG melting from the current.

Granted, with networking equipment, we are only talking about small volts and amps... nothing to really worry about I guess. Just over thinking this I guess.

Sent from my Samsung using Tapatalk
__________________
"If the women don't find you handsome, they should at least find you handy!"
Kevin_Essiambre is offline   Reply With Quote
Old 05-21-2019, 05:54 PM   #6
Hackenschmidt
 
splatz's Avatar
 
Join Date: May 2015
Location: Parts Unknown
Posts: 8,155
Rewards Points: 3,704
Default

I would bond it, even though it's very possible it will never matter. If there's a piece of equipment with power cord with a ground, and the metallic case of the equipment is bonded to cord ground, the rack will be grounded. However what if they swap out for equipment with a two prong plug in the future or etc., then the rack is floating.

So the rack is floating, so what? Well, if there is any shielded cable terminated in a patch panel or etc., the patch panel will expect the rack to provide a ground path. For example, maybe you have just a cable modem / router (two wire power cord, no ground, plastic case) - if the rack is grounded, you can simply install a grounding block on the rack and run the coax through that and all is well. Especially important if you want to use a surge protector on the coax, most of those rely on the shield being grounded.

Longshot, but if the cable shield ever comes in contact with line voltage, the shield gives you a path to clear the fault.

Under normal circumstances, some communications equipment may bootleg the EGC for ground reference (I say bootleg because they should be using the signal ground, but this isn't always the case.) Some communications equipment will be more noise / interference resistant when the equipment is equipotentially bonded.
glen1971 and Kevin_Essiambre like this.
__________________
Everything Should Be Made as Simple as Possible, But Not Simpler
splatz is online now   Reply With Quote
Old 05-22-2019, 01:21 PM   #7
Electrical Contractor
 
wcord's Avatar
 
Join Date: Jan 2011
Location: Winnipeg, Canada
Posts: 3,784
Rewards Points: 1,524
Default

If you mount a metal outlet box onto the metal of the rack then it is considered. If the the outlet is beside the rack and you just have the plug-in cords running over, then you have to run a number 6 from your outlet box to the metal of the rack
Kevin_Essiambre likes this.
__________________
Nothing is to be gained by arguing with fools.
Nothing can be gained by reasoning with ignorant people.
wcord is offline   Reply With Quote
The Following User Says Thank You to wcord For This Useful Post:
Kevin_Essiambre (05-22-2019)
Old 05-22-2019, 03:56 PM   #8
Senior Member
 
Join Date: Mar 2010
Location: Welland, Ontario Canada
Posts: 2,062
Rewards Points: 3,840
Default

Bonding the rack is just not for electrical bond, but for static bond. Often the datacenters are very dry and as you move across the raised floor if the rack is not bonded you will get zapped and depending on the equipment it may get zapped too.

Typically we would install a copper buss plate and bring separate tails for each rack and than connect that to the system ground. It could be as easy as installing it to building steel, a distribution panel for the server room, or a wire all they back to the system ground itself.

Some equipment, such as racks without equipment (patch panels) may not have any energized equipment on them, but still potentially be energized either through POE or other external sources. Video equipment seems to be the most vulnerable as the people installing that stuff do not understand the principle of potential difference and just start stringing cat6 all over and connecting cameras from separate power sources...

Cheers
John
splatz likes this.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Navyguy is offline   Reply With Quote
The Following User Says Thank You to Navyguy For This Useful Post:
Kevin_Essiambre (05-22-2019)
Old 05-22-2019, 07:51 PM   #9
Beam Me Up Scotty
 
Kevin_Essiambre's Avatar
 
Join Date: Feb 2017
Location: Ottawa, Ontario, Canada
Posts: 651
Rewards Points: 142
Default

Quote:
Originally Posted by wcord View Post
If you mount a metal outlet box onto the metal of the rack then it is considered. If the the outlet is beside the rack and you just have the plug-in cords running over, then you have to run a number 6 from your outlet box to the metal of the rack
So by mounting it on the rack,the 14 AWG bond wire in the AC90 cable would be a large enough bond wire?

I have no issues in running Flex and pulling a #6 bond and 2 #14 conductors.

Data racks is something you don't often find in a home set up (at least around here). This is a large custom home with NO smart home devices... the guy is paranoid about people gaining access yo his devices.

Sent from my Samsung using Tapatalk
__________________
"If the women don't find you handsome, they should at least find you handy!"
Kevin_Essiambre is offline   Reply With Quote
Old 05-23-2019, 06:02 AM   #10
Electrical Contractor
 
wcord's Avatar
 
Join Date: Jan 2011
Location: Winnipeg, Canada
Posts: 3,784
Rewards Points: 1,524
Default

Quote:
Originally Posted by Kevin_Essiambre View Post
So by mounting it on the rack,the 14 AWG bond wire in the AC90 cable would be a large enough bond wire?

I have no issues in running Flex and pulling a #6 bond and 2 #14 conductors.

Data racks is something you don't often find in a home set up (at least around here). This is a large custom home with NO smart home devices... the guy is paranoid about people gaining access yo his devices.

Sent from my Samsung using Tapatalk
That's what one of my inspectors said was acceptable. I can't see any residential setup needing much more than that.
However, most commercial specs require a #6 bond wire. We've even had static disappating flooring to connect in some projects.
splatz likes this.
__________________
Nothing is to be gained by arguing with fools.
Nothing can be gained by reasoning with ignorant people.
wcord is offline   Reply With Quote
The Following User Says Thank You to wcord For This Useful Post:
Kevin_Essiambre (05-23-2019)
Old 05-23-2019, 06:50 AM   #11
Hackenschmidt
 
splatz's Avatar
 
Join Date: May 2015
Location: Parts Unknown
Posts: 8,155
Rewards Points: 3,704
Default

There is a communications standard, TIA-607, if the specs are to that, grounding for racks etc. is really over the top, even after backing down a little in the last revision.

The #6 certainly wouldn't hurt but I am not sure what it would ever do that a normal sized #14 conductor would not, other than being physically durable. Static dissipation, equipotential for signal reference, signal ground loops, etc, would probably be handled by #24. The slightly lower impedance of the big wire for the surge protection equipment would make some theoretical difference but I am skeptical it would ever be significant.
Attached Thumbnails
Bonding of data racks-telecommunications-grounding-bonding-system.png  

__________________
Everything Should Be Made as Simple as Possible, But Not Simpler
splatz is online now   Reply With Quote
The Following User Says Thank You to splatz For This Useful Post:
Kevin_Essiambre (05-23-2019)
Old 05-23-2019, 07:42 AM   #12
RSE Master Electrician
 
Incognito's Avatar
 
Join Date: Apr 2019
Location: Ontario, Canada
Posts: 485
Rewards Points: 618
Default

It must be bonded, but the bond only needs to be sized based on the ampacity of the largest ungrounded conductor carried by or connected to it, just like cable tray.

For electrical, the bonding conductor shall not be required to be larger than the current carrying conductors.

10-614
Morty88 likes this.
__________________
2018 Ontario Electrical Code
Incognito is offline   Reply With Quote
The Following User Says Thank You to Incognito For This Useful Post:
Kevin_Essiambre (05-23-2019)
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Gec entering enclosure ElectricalArtist General Electrical Discussion 1230 02-13-2018 09:35 PM
Equipment bonding vs equipment bonding ElectricalArtist General Electrical Discussion 3 12-10-2017 07:00 AM
interesting question: what if there is no bonding between ground and neutral? mike883 General Electrical Discussion 35 05-29-2016 02:18 PM
Hydro tub Bonding? HackMaster General Electrical Discussion 2 01-30-2016 11:26 AM
Rule 10-906 meadow Canadian Electrical Forum 29 01-19-2016 06:27 PM


All times are GMT -4. The time now is 05:43 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Our Pro Sites Network
ContractorTalk.com | DrywallTalk.com | HVACSite.com | PaintTalk.com | PlumbingZone.com | RoofingTalk.com