Grounding - EMT Conduit - Code - Commerical Bldg.

[hardworker]

I am having a debate with the management of a commercial building about code.

All wiring is in EMT conduit. All runs are using AWG 12.

I am insisting on running one green ground conductor per conduit run. Whenever a connection is made within a box, I ground the box as well as the device using the green ground conductor.

Management only wants to run the green ground condutor to the beginning of each conduit run, terminate the green ground conductor to the EMT, and then only use the EMT conduit as ground for the devices down the conduit run.

Refresh my memory as far as code. Please comment.

 

[copper chopper]

emt is used as an acceptable equipment ground under most cases... what kind of building is this being done in.... if its a hospital or health care facilty then a green grounding conductor is required in most cases...

 

[jumper]

emt is used as an acceptable equipment ground under most cases... what kind of building is this being done in.... if its a hospital or health care facilty then a green grounding conductor is required in most cases...

I believe it is an insulated grounding conductor properly identified shall be ran in a metallic conduit that qualifies as a redundant EGC for 517 installs.

 

[ActionDave]

....Management only wants to run the green ground condutor to the beginning of each conduit run, terminate the green ground conductor to the EMT, and then only use the EMT conduit as ground for the devices down the conduit run.
.

Why do this? EMT is a fine EGC. Pull a green everywhere or don't. I don't. It is a waste of wire.

 

[hurk27]

250.118(4) clearly allows the EMT to serve as the EGC, and if the EMT originates from a metal box or cabinet that is bonded then there is no need to even run a green EGC to the first box or device, 517 is only required in patient care areas of health care facilities that includes dentist, and nursing homes which many forget about.

 

[flashlight]

Was always taught (25+ years ago) that it is not required but good practice to run green ground
wire in EMT, and have done ever since. According to previous post, have wasted a lot of wire over the years !

 

[PEDRO ESCOVILLA]

i'm not as big fan of no egc in emt. if there is a loose coupling, loose screw, or loose anything in your pipe run, do don't have an effective egc. i've seen the stuff come apart while trying to push a fish through it. not a run i installed mined you, but existing , in an existing building. i always put one in, unless it's rigid, even then 99 times out of 100, i pulll the green. good sleep is worth more than a little wire, you never know what someone behind you is going to do. i tend to err on the side of caution

 

[hardworker]

I am going to run the green conductor. In addition to running the green conductor and using it to ground the devices, what about also grounding the devices directly to the emt as well.

Is this overkill times 2 ?

 

[cadpoint]

....what about also grounding the devices directly to the emt as well.

Is this overkill times 2 ?

Just remove the waxed tab that are on the 6/32's, there you down to just overkill...

 

[iwire]

I am going to run the green conductor.

I love it. :lol:

You came here looking for code advice to use against 'management' when you where shown that what management wanted met code you decide to ignore it and just do what you want.

Let me ask you this, who is paying for this additional work?

Are you going to go off the clock and buy the additional wire yourself? Or are you just making management pay for things they don't want?

In my opinion that is insubordinate and you would be at the top of my layoff list.

 

[jeremysterling]

...All runs are using AWG 12.

...Is this overkill times 2 ?

Just remove the waxed tab that are on the 6/32's, there you down to just overkill...

Yes, cadpoint, overkill X2 would be pulling #10 AWG EGC!

 

[cadpoint]

The OP should take a few minutes and read all of Article 406....

 

[copper chopper]

when you say directly to the emt i assume you mean bonding it to every box.. in most cases you can bond it to the boxes and use devices with bonded screws (the ones with springs or tabs on the yoke) on them as long as its in non-exposed work such as in walls that are made of non-combustable materail.

 

[tom baker]

All wiring is in EMT conduit.

A minor point. EMT is not conduit. This point was the cause for a code change in the 2011 cycle for conduits installed above rooftops, EMT was not included in the 2008 rule, so the wording was changed to circular raceways.

 

[jaggedben]

Just to be thorough, another thing that might come into play is 250.97 Bonding for Over 250 Volts. In that case a wire EGC may be required.

 

[tkb]

Just to be thorough, another thing that might come into play is 250.97 Bonding for Over 250 Volts. In that case a wire EGC may be required.

250.97 only addresses the fittings used to bond a raceway that has conductors that are used over 250 volts to ground and not the EGC.

 

[hardworker]

I don't think this is a forum for work politics, but let me rephrase my statement to what I meant to say.

I was hired to keep the building safe. I went to the forum to get backing for what I was taught on the job. I took this info to the owner of the building and layed it out for him.

After he heard all the different facts, he agreed with me.

I appreciate this forum.

 

[jaggedben]

250.97 only addresses the fittings used to bond a raceway that has conductors that are used over 250 volts to ground and not the EGC.

Right. And while everybody in this thread has been assuming, and probably correctly, that the work in question involves voltages of 240 or less, that wasn't actually stated anywhere.

 

[jusme123]

Why do this? EMT is a fine EGC. Pull a green everywhere or don't. I don't. It is a waste of wire.

.....just make sure it is not a requirement in the specs, which makes any point of uselessness that you have moot.

 

[captainwireman]

Depends on the quality and circumstances of the installation

Depends on the quality and circumstances of the installation

Forgive my overkill. Sure, the posts will comply to NEC code but if it is a critical installation and there is any chance of vibration or some one crawling over the pipes or for that matter, anything that may disturb the original installation, these conduits may seperate so that's my 2 cents.