Utility Contractor Installing Parking Lot Lighting

[kwired]

I wasn't trying to say it is any safer because it is own and maintained by the utility, I was just pointing out that these POA's are not told of the difference in the two code requirements and that because of the dangers of this type of wiring the added liability of taking owner ship of such an installation without bringing it up to the NEC requirements, they don't even know that the way the utilities wire these street lights don't meet the NEC much less that they are very dangerous and could possibly cause a high liability risk as well as possibly of having their home owners, children, as well as their pets at risk if the wiring is not brought up to the NEC requirements.

The problem is most not in the electrical trade would have no idea of this difference and these property owners as well as the POA's are choosing to purchase these systems from the utility's to lower the monthly cost of leasing/renting the lights and poles from the utility, but they are not being told that in doing so the wiring of them needs to be changed.

I clearly stated in my post how dangerous these systems are no matter who own them.

If you were not an electrical professional would any of that make any sense to you? Electric utility can install one way and it is presumably safe, but if ownership of it changes all of a sudden it is not safe and must follow different installation standards?

True the biggest difference here is not what is safer but who holds the liability. You would think the POCO's operating such an install would take liability into consideration when it comes to choosing the installation method whether they are held to a particular code or not.

 

[mivey]

If the install is on a typical wood pole, that is not really a problem, but it becomes a big safety problem when metal poles are installed without a fault return path.

For normal conductor that is no doubt. Some use the neutral for the return.

There have been a number or cases where the utility or municipality has had to pay big settlements from cases like this. The fact that an unsafe installation is permitted or required by the NESC is not a valid defense.

An unsafe installation is not permitted nor required. If the system can't clear the fault is a reasonable amount of time, they are not complying with the NESC.

 

[mivey]

We have seen news reports over the years of people and pets being killed because of this method of wiring, how many people must die before someone gets the NESC to change the way the stand alone metal poles are wired, even a fuse would help but it will not stop the pole from being energized if the neutral is lost, or having a voltage drop on the neutral being imposed on the pole.

I think it is more a matter of getting them to understand what is required.

The argument about who should rule (NEC or NESC) is what I was addressing. For the utility, the NESC rules and a safe install can be made if they follow the NESC. If there is a failure to be safe, then obviously they need to change what they are doing.

But saying that following the NEC is the only way to go is not going to fly. One could look at the two ground-rod requirement (which is a complete farce) and say that the NEC is unsafe and we should all follow the NESC. The two codes are for two separate arenas and we should work within the codes to be safe, not just jump back and forth between codes because we don't like how someone is handling a particular install.

 

[hurk27]

For normal conductor that is no doubt. Some use the neutral for the return.

An unsafe installation is not permitted nor required. If the system can't clear the fault is a reasonable amount of time, they are not complying with the NESC.

Clearing a fault is not the issue, even though many of these street lights are being tapped to the transformers secondaries without any OCPD's, the main issue is the fact that they are using the grounded conductor as the fault clearing path, and because this conductor also carries normal load current you have the danger of electrifying the grounding of the metal pole if the grounded conductor looses connection or in the case of no OCPD is burned open when there is a fault, not only to add that the voltage drop on long strings of lights will also raise the voltage of anything that is bonded to this grounded conductor above the Earth, depending upon how long the circuit run is and the size of the conductors are, we have read in this thread that it is common for some POCO's to use a 12/2 cable, the string of lights I saw was hundreds of feet long, maybe over a thousand feet, the voltage drop at the end fixture on the neutral could have been as much as 10 volts with the fixtures being 250 watt HPS, this voltage can double when the fixtures start up as they draw twice the current when starting, also what if a person was leaning against the pole with bare feet at the time a line to neutral fault happened, the voltage could reach close to the circuit voltage if the 12/2 has a high enough resistance in this long run.

This is why the neutral should never be used as a ground fault path when the metal grounded parts of a pole or equipment can be contacted by a person who also can contact the Earth.

I think it is more a matter of getting them to understand what is required.

The argument about who should rule (NEC or NESC) is what I was addressing. For the utility, the NESC rules and a safe install can be made if they follow the NESC. If there is a failure to be safe, then obviously they need to change what they are doing.

But saying that following the NEC is the only way to go is not going to fly. One could look at the two ground-rod requirement (which is a complete farce) and say that the NEC is unsafe and we should all follow the NESC. The two codes are for two separate arenas and we should work within the codes to be safe, not just jump back and forth between codes because we don't like how someone is handling a particular install.

saying a safe install can be made is like saying that there is nothing wrong with using the neutral as a EGC, I hope you do not believe this? unless you are agreeing that a separate EGC needs to be run?

Only a separate non-current carrying conductor that does not have a path through a load to a conductor that has a voltage potential to Earth (hot/ungrounded conductor) this is what an EGC is and is why the NEC requires it.

We all know that the grounded conductor (neutral) will become the potential of the hot when the connection is lost at the source end, and anything bonded to it will also become hot in reference to earth.

I don't know if the NESC requires fusing at the source for these street lights, but I see many up on poles just tapped to what ever secondaries that might be located on the pole or several poles down, I know most pole mounted street lights that are up on the pole are done this way without any OCPD's, the problem is many linemen are carrying this method over to metal ground mounted poles that a person could be in contact with it and Earth, and because they use the grounded current carrying conductor as the fault bond to the metal pole it becomes even more of a hazard.

I talked to a lineman about this and asked him what would happen if the grounded conductor opened up, and his response was shocking literally, he didn't have a clue that the voltage of the ungrounded conductor would flow through the load and energize the grounded conductor and the pole, and when I got him to understand that part, he made the commit that the ground rod at the pole should keep it at earth potential, when I told him that the ground rod could not do this, and showed him that even at 25 ohms it would not pass more then 4.8 amps, and if the load on the circuit pulled more then this you would still have close to 120 volts on the pole, he then couldn't believe this was allowed, he said they never taught them anything like this in training, so its no wonder that many linemen don't have a clue on how dangerous this can be, they are being taught that all you have to do is install a ground rod and everything is safe, and we see this with them requiring a ground rod at services even though we have other electrodes that far exceed what a rod could ever do.

As I said before and Don has pointed out, light fixtures up on wooden poles or other insulated type oles, where a person would not have a way to make contact between the fixture and Earth I have no problem with using the grounded conductor as a fault path, but not when it is down close to Earth on a metal pole.

 

[kwired]

.

I talked to a lineman about this and asked him what would happen if the grounded conductor opened up, and his response was shocking literally, he didn't have a clue that the voltage of the ungrounded conductor would flow through the load and energize the grounded conductor and the pole, and when I got him to understand that part, he made the commit that the ground rod at the pole should keep it at earth potential, when I told him that the ground rod could not do this, and showed him that even at 25 ohms it would not pass more then 4.8 amps, and if the load on the circuit pulled more then this you would still have close to 120 volts on the pole, he then couldn't believe this was allowed, he said they never taught them anything like this in training, so its no wonder that many linemen don't have a clue on how dangerous this can be, they are being taught that all you have to do is install a ground rod and everything is safe, and we see this with them requiring a ground rod at services even though we have other electrodes that far exceed what a rod could ever do.

As I said before and Don has pointed out, light fixtures up on wooden poles or other insulated type oles, where a person would not have a way to make contact between the fixture and Earth I have no problem with using the grounded conductor as a fault path, but not when it is down close to Earth on a metal pole.

Linemen don't have a clue because their training is more focused on over 600 volts. The ground rod is more effective at clearing faults at higher voltages.

Other problem with wood poles is if they run a bare exposed GEC down the side of the pole to a ground rod, then this is still something that could be subject to contact by people if it should become energized. If same pole has primary conductors on it then it likely has a ground rod. If there are secondary conductors only attached to the pole, often there is a rod but sometimes there is not.

 

[mivey]

the main issue is the fact that they are using the grounded conductor as the fault clearing path

And we do that on most of the main line. Not really my preference for secondary taps. Actually I prefer to not carry a ground from the transformer to a remote location.

and because this conductor also carries normal load current you have the danger of electrifying the grounding of the metal pole if the grounded conductor looses connection

and that is what we have when we do not carry a ground, which is the preferred method. You have to consider bonding and GPR.

not only to add that the voltage drop on long strings of lights will also raise the voltage of anything that is bonded to this grounded conductor above the Earth

The better method is to keep the neutral isolated, ground at the pole but do not bring a ground from the transformer but use an RCD instead.

depending upon how long the circuit run is and the size of the conductors are, we have read in this thread that it is common for some POCO's to use a 12/2 cable, the string of lights I saw was hundreds of feet long, maybe over a thousand feet, the voltage drop at the end fixture on the neutral could have been as much as 10 volts with the fixtures being 250 watt HPS, this voltage can double when the fixtures start up as they draw twice the current when starting,

Yeah, we can come up with bad installation scenarios all day long, both for NESC and NEC installs.

also what if a person was leaning against the pole with bare feet at the time a line to neutral fault happened, the voltage could reach close to the circuit voltage if the 12/2 has a high enough resistance in this long run.

and what do you think the GPR will be at their feet? I can assure you it will be much less than the hundreds of volts they can get across their body from transferred potential. I do think an RCD is a better way to go. Running a ground wire to a remote location raises the danger of transferred potentials.

This is why the neutral should never be used as a ground fault path when the metal grounded parts of a pole or equipment can be contacted by a person who also can contact the Earth.

Contacting remote earth through other grounded metals is more of an issue and is what bonding covers. When bonding won't work because there is remotely grounded metal everywhere, an RCD should be used.

saying a safe install can be made is like saying that there is nothing wrong with using the neutral as a EGC, I hope you do not believe this?

It works for many cases. Our secondary system on the main line and taps to services operate just like that.

Keep in mind that there is no such thing as safe. Safe is a relative term and is weighed against cost. I hope you do not believe a ground on an NEC install makes it a safe install as it only makes it safe with caveats.

unless you are agreeing that a separate EGC needs to be run?

No. That only introduces danger from transferred potential. That is a bigger concern in the NESC world.

Only a separate non-current carrying conductor that does not have a path through a load to a conductor that has a voltage potential to Earth (hot/ungrounded conductor) this is what an EGC is and is why the NEC requires it.

The NESC world is a different arena.

We all know that the grounded conductor (neutral) will become the potential of the hot when the connection is lost at the source end, and anything bonded to it will also become hot in reference to earth.

to remote earth.

I don't know if the NESC requires fusing at the source for these street lights, but I see many up on poles just tapped to what ever secondaries that might be located on the pole or several poles down, I know most pole mounted street lights that are up on the pole are done this way without any OCPD's, the problem is many linemen are carrying this method over to metal ground mounted poles that a person could be in contact with it and Earth, and because they use the grounded current carrying conductor as the fault bond to the metal pole it becomes even more of a hazard.

Most I see do not bond the neutral to the pole and the neutral is isolated from the pole ground.

I talked to a lineman about this and asked him what would happen if the grounded conductor opened up, and his response was shocking literally, he didn't have a clue that the voltage of the ungrounded conductor would flow through the load and energize the grounded conductor and the pole, and when I got him to understand that part, he made the commit that the ground rod at the pole should keep it at earth potential, when I told him that the ground rod could not do this, and showed him that even at 25 ohms it would not pass more then 4.8 amps, and if the load on the circuit pulled more then this you would still have close to 120 volts on the pole, he then couldn't believe this was allowed, he said they never taught them anything like this in training, so its no wonder that many linemen don't have a clue on how dangerous this can be, they are being taught that all you have to do is install a ground rod and everything is safe,

Not suprising since most linemen don't understand the details of how things work anyway. That is no different than most electricians not having a clue about how things work either. Only a few make the effort to actually understand.

and we see this with them requiring a ground rod at services even though we have other electrodes that far exceed what a rod could ever do.

I don't doubt that a bit.

As I said before and Don has pointed out, light fixtures up on wooden poles or other insulated type oles, where a person would not have a way to make contact between the fixture and Earth I have no problem with using the grounded conductor as a fault path, but not when it is down close to Earth on a metal pole.

I think you should be more concerned about them making contact with other metal objects. Contact with local earth is a design issue. There are many installs that probably should have RCD devices but do not and it really depends on the GPR, surface resistance, touch potentials, etc.

 

[mivey]

Linemen don't have a clue because their training is more focused on over 600 volts. The ground rod is more effective at clearing faults at higher voltages.

FWIW, most linemen don't "have a clue" about over 600 volts either. Their focus is not on how it works and that does not mean they are clueless.

I could say you are clueless about LV also but the fact is you are only clueless about the concerns on a utility system, not clueless about LV in general.

Keep in mind that linemen also work with LV. In fact, for some utilities, the LV system may cover as much as 50% of the area covered by the MV system.

 

[kwired]

FWIW, most linemen don't "have a clue" about over 600 volts either. Their focus is not on how it works and that does not mean they are clueless.

I could say you are clueless about LV also but the fact is you are only clueless about the concerns on a utility system, not clueless about LV in general.

Keep in mind that linemen also work with LV. In fact, for some utilities, the LV system may cover as much as 50% of the area covered by the MV system.

I will not disagree with what you said here. I will just say that the average lineman does not need to depend on too much of the finer details of electrical theory. They may not even remember specifically what Ohm's Law is yet do remember the concept.

Most of these guys see conductors smaller than 6AWG to be like learning a foreign language.

I may understand the theory of how their distribution system works, but would not even attempt to do some of what they do without some help from someone with more experience in this area, and definitely don't know all the training they have with operating around live medium and high voltage equipment.

 

[mivey]

I will just say that the average lineman does not need to depend on too much of the finer details of electrical theory. They may not even remember specifically what Ohm's Law is yet do remember the concept.

Same is true for the average electrician.

Most of these guys see conductors smaller than 6AWG to be like learning a foreign language.

Far from the truth. They install and maintain many miles of smaller conductor, including those used in power, controls, and metering.

I may understand the theory of how their distribution system works

I think you understand some but probably not as much as you think.

but would not even attempt to do some of what they do without some help from someone with more experience in this area, and definitely don't know all the training they have with operating around live medium and high voltage equipment.

I'm with you there partner. As much as I can, I like to leave the MV & HV work to those that do it everyday and I want them with me when I have to get close.

 

[iwire]

Far from the truth. They install and maintain many miles of smaller conductor, including those used in power, controls, and metering.

Linemen?

Not the ones I run into out on the job.

 

[mivey]

Linemen?

yes

the ones I run into out on the job.

Some linemen are very bright and will excel given the opportunity. There are varying degrees of ability and perhaps you only get exposed to a select group or maybe the utilties you deal with limit the scope of their work.

 

[kwired]

Most controls and metering done by POCO are done by specific individuals around here and not whichever general "lineman" is available. Metering and controls is the majority of what these people do on a daily basis.


When I said I understand the theory of how their distribution system works, I did not mean I was qualified to step in and start operating and maintaining it. The basics of the distribution is not a whole lot different than distribution within a facility. You have sources, loads, conductors, switches overcurrent devices, just like inside a facility. Some of the details involved and design specifications are going to be different, but basic electricity 101 applies to both areas. Electricity 202, or 303 starts to differ between each area.

 

[iwire]

yes


Some linemen are very bright and will excel given the opportunity. There are varying degrees of ability and perhaps you only get exposed to a select group or maybe the utilties you deal with limit the scope of their work.

Around here linemen do not do the things you speak of, everything is very departmentalized.

We have overhead crews, underground crews, metering crews, even water crews to handle pumping out underground facilities.

Just a couple of weeks ago I was involved in replacing primaries from a pole to a pad mount. Keep in mind a contractor working for us was doing the actual replacement of the conductors but it still required three trucks from the power company. A supervisor, a truck from the crew that makes up cut outs and another truck to open and closet the cut outs.

The linemen who do the overhead work around here while very hard working and out on the job in the worst weather conditions have never struck me as knowing much more than line construction.

 

[mivey]

Most controls and metering done by POCO are done by specific individuals around here and not whichever general "lineman" is available. Metering and controls is the majority of what these people do on a daily basis.

That is true in many places. Even where it is not, you have "A" crews, "B" crews, etc that have different grades of abilities.

When I said I understand the theory of how their distribution system works, I did not mean I was qualified to step in and start operating and maintaining it. The basics of the distribution is not a whole lot different than distribution within a facility. You have sources, loads, conductors, switches overcurrent devices, just like inside a facility. Some of the details involved and design specifications are going to be different, but basic electricity 101 applies to both areas.

Yes basic electrical theory applies in many disciplines. Here we were discussing protection and control which is not 101.

Electricity 202, or 303 starts to differ between each area.

For sure. and 404, 505, 606, ... I keep finding more things to learn as I go. I wish I knew 1/2 of what I wanted to know and knew what else I wanted to know that I don't know I don't know. Where is Rumsfeld when you need him?

 

[mivey]

Around here linemen do not do the things you speak of, everything is very departmentalized.

I lot of times the bigger the utility the more it gets like that. Even with the bigger utilities, you might find the more experienced crews in the remote areas for obvious reasons. They are the go-to guys when things get complicated or you can't hold their hand or when you need to get someone more training.

The linemen who do the overhead work around here while very hard working and out on the job in the worst weather conditions have never struck me as knowing much more than line construction.

But I would be willing to bet that some of the linemen have rotated through different departments and can do more. Some of the guys are really not interested in doing different things, some simply can't.

 

[GoldDigger]

But I would be willing to bet that some of the linemen have rotated through different departments and can do more. Some of the guys are really not interested in doing different things, some simply can't.

...And have the wisdom to know the difference?

 

[mivey]

...And have the wisdom to know the difference?

Sometimes, if they listen. The guys tend to be brutally honest with each other sooner or later.

 

[San -Brooke]

If a private Electrical Contractor is installing parking lot lights on private property subcontrated by the local utility in my personal opinion it should be installed per NEC and inspected and the installation supervised by a licensed electrician per KRS 227A.020(4)(Kentucky) A person who is not licensed as an electrical contractor, electrician, or master electrician shall not engage in any activities or perform any of the duties usually performed by an electrical contractor, electrician, or master electrician unless the unlicensed person is under the direct supervision of a licensed electrician or master electrician who is present on the site where the work is being performed.

I believe our local utility company and it's sub-contractor has far exceeded what is exempt under NEC 90.2(B)

 

[mivey]

If a private Electrical Contractor is installing parking lot lights on private property subcontrated by the local utility in my personal opinion it should be installed per NEC and inspected and the installation supervised by a licensed electrician per KRS 227A.020(4)(Kentucky)

Not if it is operated and maintained by the utility as an extension of their system. The subcontractor follows the utility guidelines and the install will be approved through the utility's process. A subcontractor for the utility working on NESC installs does not perform "duties usually performed by an electrical contractor, electrician, or master electrician".

If it comes from the customer's switchgear, then the utility is just another contractor and must abide by the NEC.

I believe our local utility company and it's sub-contractor has far exceeded what is exempt under NEC 90.2(B)

I see that sometimes where the linemen think they can be electricians without a license and do some work on the side. Usually results in a bunch of jack-leg stuff.

 

[San -Brooke]

Not if it is operated and maintained by the utility as an extension of their system. The subcontractor follows the utility guidelines and the install will be approved through the utility's process. A subcontractor for the utility working on NESC installs does not perform "duties usually performed by an electrical contractor, electrician, or master electrician".

Please do tell where in NEC 90.2(B) it allows that or anywhere in the NESC it contradicts NEC 90.2(B) on this issue? And or negates specifically what it says in NEC 90.2(A)(4)