old conduit

[dshelley]

I am rerouting a air conditioners power through and old conduit system the old conduit system does not have a ground do I need to run a ground according to the 99 code change that requires a ground be ran with every conduit.

 

[infinity]

What kind of conduit? Some metallic raceways can serve as the EGC. No additional wire type EGC would be required in many metallic raceways.

 

[augie47]

I'm unaware of any change that requires a ground be run with every conduit.
If the conduit meets the requirements of 250.118 it is a grounding conductor.
If you are unaware of the condition of the conduit and its couplings etc or if you wish to add a grounding conductor to give you a "warm-fuzzy" feeling, feel free, but there is no requirement that I know of.

 

[220wire]

The piece of LFMC may need a ground in it. I've never understood why GEC's don't get pulled in. Maybe contractors are just big tight-**** now days because of the economy they can't spare the 10$. I can't remember ever not pulling a GEC. On the other hand if you didn't install the conduit and can't access the entire conduit run, how can you ensure that all the couplings are tight?

 

[LawnGuyLandSparky]

The piece of LFMC may need a ground in it. I've never understood why GEC's don't get pulled in. Maybe contractors are just big tight-asses now days because of the economy they can't spare the 10$. I can't remember ever not pulling a GEC. On the other hand if you didn't install the conduit and can't access the entire conduit run, how can you ensure that all the couplings are tight?

You can do a load test. Don't villianize contractors for not installing a redundant GEC to a danged unit heater. It's a unit heater, not a dialysis machine...

 

[220wire]

You can do a load test. Don't villianize contractors for not installing a redundant GEC to a danged unit heater. It's a unit heater, not a dialysis machine...

villanize wouldn't be my choice of words... I think cheap, lazy, and hard-headed come to mind. I know this has been debated up and down on the forum and there is no politcaly correct answer to satisfy everyone opinion. But if I install it, it gets a ground. The way you do it isn't wrong it's just plan-b for me when I'm 100 miles from the parts house and didn't bring enough. BTW have you ever noticed that there isn't an electrician out there who won't give you their opinion?

 

[LawnGuyLandSparky]

villanize wouldn't be my choice of words... I think cheap, lazy, and hard-headed come to mind. I know this has been debated up and down on the forum and there is no politcaly correct answer to satisfy everyone opinion. But if I install it, it gets a ground. The way you do it isn't wrong it's just plan-b for me when I'm 100 miles from the parts house and didn't bring enough. BTW have you ever noticed that there isn't an electrician out there who won't give you their opinion?

It's all good 220. I have a hard time justifying pulling grounds when your pipe rack consists of 40--120 3/4 EMT on a 3-level kindorf rack strapped every 7-9 foot... and yes, when individual HR's peel off towards the load I DO trust that all the couplings are tight.

 

[220wire]

we need the picture from the other topic that has the guy getting shocked by the light pole without a GEC

 

[roger]

we need the picture from the other topic that has the guy getting shocked by the light pole without a GEC

Metallic conduit is an Equipment Grounding Conductor and is sufficient. (note EGC)

Per commentary in NFPA 99, metallic conduit is noted as being the superior EGC as compared to the insulated conductor, see 517.13(A)&(B)

Roger

 

[LawnGuyLandSparky]

we need the picture from the other topic that has the guy getting shocked by the light pole without a GEC

 

[220wire]

EGC there you go! Wouldn't it be a GEC for connecting grounded conductors on a detached building? EGC definately for branch circuits. Thanks

 

[roger]

Wouldn't it be a GEC for connecting grounded conductors on a detached building? EGC definately for branch circuits. Thanks

No, the low impedance path to the detached building for fault clearing would still be an EGC, a Grounding Electrode Conductor only connects to a Grounding Electrode and at the voltages we deal with does practically nothing for pesonel safety. The reason we Ground (earth) systems per the NEC is only for stabilizing voltage to earth, lightning, and HV surges.

See 250.4(A)(1)

Roger

 

[tom baker]

Metallic conduit is an Equipment Grounding Conductor and is sufficient. (note EGC)

Per commentary in NFPA 99, metallic conduit is noted as being the superior EGC as compared to the insulated conductor, see 517.13(A)&(B)

Roger

And, the CMPs would add, if there is a loose fitting, its a workmanship issue and not a product issue. Remember, there are mfg reps on the CMPs....

 

[220wire]

So in a detached building the grounded conductor is isolated from the EGC. Or are they bonded to one another at the point of service? Maybe I should just refer to the green wire or the white wire. Much easier
Sorry for getting so off topic here

 

[lakee911]

I'd install it for peace of mind...

 

[Still Learning]

Hi Guys -

My first post on this forum, though I've used it as a reference for years. After reading this thread I just had to comment. Over the past 25 years as a consulting engineer, I've seen numerous problems due to EMT used as an EGC. Compression and set screw connections tend to fall prey to corrosion and just don't stand the test of time. I'm surprised at the strong defense of this practice. It makes no difference what the load is, the lack of a dependable EGC is unsafe. In closing, I'd like to note that just because an installation is code compliant, it is not necessarily good design.

Cheers to all.