Pulling new wire/cables in conduit with existing 120V energized wire/cable.

[electrofelon]

I don't know anything about the protocols at a nuke but in commercial work this is done all of the time. We usually pull out the EGC and use it to pull in the additional conductors (+new EGC) while the circuits are energized. Using an insulated EGC as a pull line for additional insulated conductors limits the possibly of damaging the existing conductors to near zero.,

Yup, did exactly that just three days ago. Worked like a charm.

 

[Ken_S]

I've spoken to many guys who have worked at our local nuke plant, nothing is done without explicit instructions on how to do it. Not even a hole can be drilled without engineering approval. So I find it hard to believe that you've been tasked with work and no instructions in that environment.

 

[Fred B]

I've spoken to many guys who have worked at our local nuke plant, nothing is done without explicit instructions on how to do it. Not even a hole can be drilled without engineering approval. So I find it hard to believe that you've been tasked with work and no instructions in that environment.

Russia? Maybe will.

Not sure of that particular environment but I know a lot of medium size companies that will hire outside help to circumvent safety requirements and push to perform work in a manner that they aren't willing to in house for fear of insurance or OSHA.

 

[Ken_S]

Russia? Maybe will.

Not sure of that particular environment but I know a lot of medium size companies that will hire outside help to circumvent safety requirements and push to perform work in a manner that they aren't willing to in house for fear of insurance or OSHA.

I deal with that mentality at work, and I really don't believe that it will hold water in a courtroom.

 

[Fred B]

I deal with that mentality at work, and I really don't believe that it will hold water in a courtroom.

Probably not, but there is enough out there willing and hungry enough to do it, that it continues, until they are caught and shut down by big brother.

 

[BillyMac59]

I don't know the law of the land where Fred B is from, but here in Ontario, Canada, hiring an outside contractor to circumvent/ignore your inhouse safety protocols as well as any provincial legislation, would amount to criminal negligence in the coutroom.

 

[petersonra]

Sorry but I would totally disagree with that procedure. Totally wrong and dangerous!

What is wrong about it? What is dangerous about it? I've seen this done can't tell you how many times. It is much much safer than trying to push a fish tape through.

 

[LarryFine]

I deal with that mentality at work, and I really don't believe that it will hold water in a courtroom.

 

[electrofelon]

Not sure of that particular environment but I know a lot of medium size companies that will hire outside help to circumvent safety requirements and push to perform work in a manner that they aren't willing to in house for fear of insurance or OSHA.

I deal with that mentality at work, and I really don't believe that it will hold water in a courtroom.

I don't know the law of the land where Fred B is from, but here in Ontario, Canada, hiring an outside contractor to circumvent/ignore your inhouse safety protocols as well as any provincial legislation, would amount to criminal negligence in the coutroom.

I think some of you are being overly dramatic about this. If some entity wants to hire a sub contractor, as long as there is nothing illegal done there is nothing that "won't hold up on Court". I don't see why a sub would have to follow some "in house safety protocols" if they are not told they must. If the sub is an owner than he doesn't have to follow OSHA. We all sub out stuff because we don't want the hassle and liability.

 

[Strathead]

Was involved where we had done an install and the original pull was effortless and w/o issues. Some time later two conductors had to be added, during this recall musing what was the effect on the existing cables.....didnt appear to be a big deal as far as pull effort etc.

Years later (because some other equipment installation issues), we had to reroute that particular conduit, so in with a new and all new wires; determ the former and remove blah blah.

Crew got to looking at the insulation on that removed conduit and shu nuff there were signs of damage where one (or more) cable apparently continued to pass that same point on that existing wire. Interestingly one group pointed to that as a proof to not do the 'pull some more' technique while the c'est la vie folks said yeah but that scuffing / skiving was not really that bad.

~

I can see the contention described: one doesnt really know until after the second pull is done and then pull em all out to see if'n there was damage, which kind of defeats any savings of time.

The moral I see to this story is, wires were pulled. They operated for years, and then new wires were pulled. And everyone lived happily ever after.

 

[BillyMac59]

I think some of you are being overly dramatic about this. If some entity wants to hire a sub contractor, as long as there is nothing illegal done there is nothing that "won't hold up on Court". I don't see why a sub would have to follow some "in house safety protocols" if they are not told they must. If the sub is an owner than he doesn't have to follow OSHA. We all sub out stuff because we don't want the hassle and liability.

I can appreciate your thoughts on this but, at least in Canada, you would be wrong. Hiring a subcontractor to avoid hassle and liability is a little misguided. Following "in house safety protocols" is an industrial standard. It has nothing to do with the subs ability and everything to do with an employer's liability.

 

[garbo]

Is it safe and legal per code to perform a push by with new cables in a conduit that has an existing energized cable.

We had several of the nylon insulated fish tapes but I preferred to just use the existing ground wire to pull in additional conductors. The few times that I did it with PVC conduit would run a temporary ground wire . Every place that I worked we always spent a little extra and only used stranded #12 &#14 guage THHN/THWN building wire. Made long pulls a lot easier. One chief electrician liked to use the smallest conduit when we had to pull over 28 wires for a bank of solenoids .Even with wire lube pulling that many #16 stranded wires thru over 150' of 3/4" conduit with 360 degrees in bends was not fun.Have pulled extra wires thru conduit that had live 480 volt wires but never had a problem. By all means always LOTO power when possible before pulling in extra wires. Smart large hospital that I retired from had a requirement of not allowing no shared grounded conductors ( ya neutrals ) and demanded that all conduit leaving a 120/208 & 480/277 panels be 1" EMT minimum and had to use #10 copper wires to first JB for all 20 amp circuits. Would pay extra to have contractor pull believe it was 9 #10 white or gray grounded conductors along with 9 #10 wires and a #10 ground wire to first always a large JB. Made adding additional circuits so much faster.

 

[jap]

It's not about getting shocked, it's about the chance you are taking of damaging the existing conductors.

This can happen whether the circuits are energized or not.

Only difference is if you find out you've damaged the conductors while you're making the pull or when you go to turn the breaker back on.

Using a fiberglass fish tape may make it easier to push past the existing conductors in the conduit, but, it's not going to keep the existing energized conductors from rubbing up against something sharp and shorting out.

The heat generated by the short circuit if this happens inside a raceway or junction box where conductors are in close proximity to each other generally destroys everything around it by the time the breaker decides to trip.

With that being said, if you do commercial or industrial work, you'll be faced with the decision of how to safely install new conductors along side existing energized conductors one way or another on a daily basis.

JAP>

 

[electrofelon]

I can appreciate your thoughts on this but, at least in Canada, you would be wrong. Hiring a subcontractor to avoid hassle and liability is a little misguided. Following "in house safety protocols" is an industrial standard. It has nothing to do with the subs ability and everything to do with an employer's liability.

Doesn't sound like any of that is illegal to me. There was a recent thread on excavating trenches and some EC said they dont want the liability so they sub it out. We all do that all the time

 

[mtnelect]

My experience is with traffic signal wiring:
1. Pull all the wiring out first.
2. Inspect and untangle the existing wiring.
3. Clean out the conduit with compressed air and water.
4. Add the additional wiring and repull.

 

[jap]

My experience is with traffic signal wiring:
1. Pull all the wiring out first.
2. Inspect and untangle the existing wiring.
3. Clean out the conduit with compressed air and water.
4. Add the additional wiring and repull.

Call the local police department for traffic control,
then,
1
2
3
4...



Jap>

 

[LarryFine]

Doesn't sound like any of that is illegal to me. There was a recent thread on excavating trenches and some EC said they dont want the liability so they sub it out. We all do that all the time

Yes, but to make the comparison apply, would the trenching sub-contractor have to follow the same safety rules that an employed trencher would?

 

[electrofelon]

Yes, but to make the comparison apply, would the trenching sub-contractor have to follow the same safety rules that an employed trencher would?

It depends. A lot of "safety rules" are company policy and have no legal basis. There is OSHA of course but that doesn't apply to those who are self employed. I am not a lawyer and I don't know if a sub contractor messes up if the hiring contractor can be held liable, but I would say it's sort of doesn't really matter because the insurance companies will hash it out.

 

[Strathead]

Yes, but to make the comparison apply, would the trenching sub-contractor have to follow the same safety rules that an employed trencher would?

When one is set up for a certain repetitive task they can do things cheaper. A utility underground company may very well have a directional boring machine, trenchers, earth vacuum, etc. These cost less when they are operating all the time, than when they sit around and are used occasionally, for example.

 

[Fred B]

Yes, but to make the comparison apply, would the trenching sub-contractor have to follow the same safety rules that an employed trencher would?

Theoretically yes, but in practice around me, No. GC knows safety (legal OSHA) requirements, but chooses in order to cut costs to overlook this as he is not liable (or thinks not) for the safety shortcomings of the sub's workers. (Not speaking about actual installation safety.) Seems more so in small/medium companies than larger. Probably more are looking over the shoulders of the large company.