Ground Wire

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Alwayslearningelec

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How many of you guys would not run the ground and use the conduit as the ground? Or what would determine( besides spec) whether or not you run the ground?
 

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We just about always include a wire type equipment grounding conductor in metallic raceways. Although we are careful to always properly tighten all fittings & locknuts, things can change or degrade over time and the wire helps to ensure a safe and effective fault current path.
 
My amateur take on this is that it's a belt-and-suspenders kind of discussion. The screw connections making little dimples in the pipe to hold things together and make the connection (ignoring the pipe touching the fitting) seems a little wimpy.

Arguments have been made that in earthquake territory the wired ground would stay attached even if the conduit pulled apart.
 
horsegoer said:
How many of you guys would not run the ground and use the conduit as the ground? Or what would determine( besides spec) whether or not you run the ground?
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For us they get what they're paying for. If they do not spec EGC's in a metallic raceway they don't get them.
 
drcampbell said:
Hear here. I would be very reluctant to spec "no EGC" unless all the conduit connections were compression type. Even then, box connectors don't instill a lot of confidence.
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As someone who has installed thousands of both types, and just as importantly, someone who has demoed almost as many while working on remodels I can say with all certainty that set screw type fittings are better than compression.
 
PaulMmn said:
My amateur take on this is that it's a belt-and-suspenders kind of discussion. The screw connections making little dimples in the pipe to hold things together and make the connection (ignoring the pipe touching the fitting) seems a little wimpy.

Arguments have been made that in earthquake territory the wired ground would stay attached even if the conduit pulled apart.
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Amateur indeed.

Let's think about this belt and suspenders for a bit. I've got steel conduit tied to steel supports that are anchored to steel framing. Even if half the fittings were left loose on purpose there is still continuity back to the panel and a little wire in the pipe isn't making anything better.

A bigger trick would be trying to isolate a piece of conduit from ground. It's near impossible.

This whole mentality that is based on nothing but an idea that a green wire makes the world safer is what led me to come up with the term Cult of the Green Wire. They have a grip on the electrical world that is impossible to escape.
 
Wooden running boards power nailed to a cement block wall. Conduit fastened to running boards dimpled all the way around the basement with outlets here and there. Stuffed with loose conductors. Transition to NM in a jbox on the way to the panel. Yes, ground is continuous.
 
ActionDave said:
Amateur indeed.

Let's think about this belt and suspenders for a bit. I've got steel conduit tied to steel supports that are anchored to steel framing. Even if half the fittings were left loose on purpose there is still continuity back to the panel and a little wire in the pipe isn't making anything better.

A bigger trick would be trying to isolate a piece of conduit from ground. It's near impossible.

This whole mentality that is based on nothing but an idea that a green wire makes the world safer is what led me to come up with the term Cult of the Green Wire. They have a grip on the electrical world that is impossible to escape.
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Unfortunately steel supports, steel framing are not approved for a ground path.
If you do commercial, you have a spec that call for grounds nearly 100% of the time. How do you get away with it?
 
The NFPA recognizes the fact that metal framing and other metal in structures combined with metallic conduit is a far better EGC than a wire, you can find this in annex A of NFPA 99.

Roger
 
cdslotz said:
Unfortunately steel supports, steel framing are not approved for a ground path.
If you do commercial, you have a spec that call for grounds nearly 100% of the time. How do you get away with it?
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I didn't say steel framing is approved or not approved, the reality is it's there.

I may have been unclear when I said I never pull a green unless someone makes me. Having a wire egc in the spec would be an example of a make me.
 
I pretty much never pull a wire egc. Fortunately, I do mostly "design/build" type of work so I can save the client from inadvertently wasting their money on a wire egc.

I'm not sure how or when bonding became this absolutely critical aspect of an electrical system. It's become just about all anyone cares about and we seem to need these layers of redundancy. Sure bonding offers a measure of improved safety, but not nearly commensurate with how it is treated.
 
electrofelon said:
I pretty much never pull a wire egc. Fortunately, I do mostly "design/build" type of work so I can save the client from inadvertently wasting their money on a wire egc.

I'm not sure how or when bonding became this absolutely critical aspect of an electrical system. It's become just about all anyone cares about and we seem to need these layers of redundancy. Sure bonding offers a measure of improved safety, but not nearly commensurate with how it is treated.
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I agree with you. I think part of it is how much press it gets.

I also think part of the reason people fall so easily into the claws of the Cult of the Green Wire is a basic lack of learning about the electrical trade....I may not really understand what makes that motor spin or how this lighting ballast works, or what the XO on the transformer is for, or whatever, but one thing I know is I can put a green wire everywhere possible and know that I am doing a great job.
 
cdslotz said:
Unfortunately steel supports, steel framing are not approved for a ground path.
If you do commercial, you have a spec that call for grounds nearly 100% of the time. How do you get away with it?
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No they are not approved, but are still very effective if your green wire fails or your raceway comes apart.

Then if you are using unistrut to rack up several raceways it ties those all together, should one raceway have a fail point, it is likely bridged around by the "rack".

If you are doing small project that was not engineered your spec may very well be your own spec. Say adding one circuit to existing facility. Many possibly will add the green wire here if the facility has green wire in everything else, but nothing really says they have to either.
 
ActionDave said:
I agree with you. I think part of it is how much press it gets.

I also think part of the reason people fall so easily into the claws of the Cult of the Green Wire is a basic lack of learning about the electrical trade....I may not really understand what makes that motor spin or how this lighting ballast works, or what the XO on the transformer is for, or whatever, but one thing I know is I can put a green wire everywhere possible and know that I am doing a great job.
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I have to agree there are many that just follow the leader and don't really learn all the technicalities of why things are the way they are or how they actually work.

A loose set screw or compression nut is installer fault. I was working on something the other day and a bonding jumper to a box had a loose bonding screw to the box, and have many times seen poorly made up wire nut type connections as well - so mistakes can and do happen even with wire type EGC's.

Most the broken coupling or connector situations I have run into likely could have been avoided with proper raceway support methods.
 
kwired said:
I have to agree there are many that just follow the leader and don't really learn all the technicalities of why things are the way they are or how they actually work.

A loose set screw or compression nut is installer fault. I was working on something the other day and a bonding jumper to a box had a loose bonding screw to the box, and have many times seen poorly made up wire nut type connections as well - so mistakes can and do happen even with wire type EGC's.

Most the broken coupling or connector situations I have run into likely could have been avoided with proper raceway support methods.
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Right. And a 'nother thing to note is, even with a wire egc, a fault inside the raceway some where will still have to follow the raceway for a ways to get back to the source so that wire egc is doing nothing for part/most of that fault anyway.
 
kwired said:
..... I was working on something the other day and a bonding jumper to a box had a loose bonding screw to the box, and have many times seen poorly made up wire nut type connections as well - so mistakes can and do happen even with wire type EGC's.
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I see it all the time, open a box and there's a wad of green wires under a nut two or three will fall out as soon as you move wires around to do your work.
Most the broken coupling or connector situations I have run into likely could have been avoided with proper raceway support methods.
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Absolutely.
 
infinity said:
For us they get what they're paying for. If they do not spec EGC's in a metallic raceway they don't get them.
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Ok so what if spec doesn't ask for it but schedule shows it like in the attached pic. They can claim they require it based on panel schedule, no?
 
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