Ungrounded feeders to street lights

[lfloyd]

I have found a subdivision with street lights supplied by 2 #8 conductors with no grounding conductor.The fixtures on each pole have been bonded to the metal pole and possibly to some sort of grounding electrode. The supply is 240 volt and each supply conductor has a fuse holder with a 5amp in-line fuse.
We also have no power to poles in some locations assumable due to damaged feeders underground.
My solution would be to have the utility company disconnect power but before I attempt something that unpopular, I wanted to solicit the opinion of others.
Anyone care to render an opinion?

 

[chris kennedy]

Are the lights owned by OPCO? Whats the wiring method?

 

[hurk27]

I have three subdivisions here with the same set up, at one time the lights were installed by the utility and monthly charged, but over time the POA purchased them to lower their bill but didn't realize that they now will have to comply with the NEC in which it doesn't, I walked E.rrr ran from them when they said they would not pay to have a EGC added to the feeders, in no way would I take that kind of liability upon myself, all it would take is one ballast to short and you will have a live pole there just waiting for a child to touch and possably be killed, a ground rod will not open the circuit and can not be depended upon to do this, these are a disaster waiting to happen.

 

[lfloyd]

The lights are owned by the City and are fed by 2 XHHW #8 copper conductors direct buried.
Why would this have ever been an acceptable installation method for utility companies with no ground return path? I have seen many things done by utility companies that did not comply with the NEC but this is the first installation I have seen that is unsafe.
Am I being overly concerned about this?

 

[texie]

Even if the lights are 240 volt are you sure one side is not grounded and all metal is bonded to that? As you know, utilities are (in general) bound not by the NEC but rather the NESC. While I am not well versed in the NESC, I think they generaly go along the lines of all metallic things bonded to the grounded conductor and not use seperate EGC. The same concept of us on the NEC do on the line side of a main disconnect. I don't think they ever do things that don't have a short circuit path to a solidly grounded conductor. I'm surprised that they would allow an installation under their rules and ownership to go into private hands that require NEC rules.

 

[Hv&Lv]

How old is this installation? You say the lights are owned by the city. Would the power also be supplied by the city(Municipal power)? The NESC has required bonding for quite a while, and the poles should have a seperate rod for each.

 

[rcarroll]

If you get the chance, there's a pretty good article on this topic in the Nov./Dec. 2011 issue of IAEI magazine.

 

[texie]

If you get the chance, there's a pretty good article on this topic in the Nov./Dec. 2011 issue of IAEI magazine.

Ron, thanks for the heads up on the IAEI article. I'm a little unclear about the discussion in the article about how the utility installs their street lights and I'm not sure the author is correct. For example, when I see a utility owned street light fed by overhead singleplex or triplex the light fixture is always bonded to the grounded conductor of the supply system. Now with underground systems it is not visibly obvious, so now I'm wondering what the NESC says. I find it hard to believe that don't have a fault return path on every thing they do. Maybe you could check this out with the FC Utility guys and enlighten us.

 

[lfloyd]

This was installed in 1986 and not by a utility company. It is metered and fed by 20 amp 2 pole breakers. There is definitely not a grounded or grounding conductor.
This was done by someone who believes a ground rod or other electrode is a ground.
I just have to decide what I'm going to do with it.

 

[texie]

This was installed in 1986 and not by a utility company. It is metered and fed by 20 amp 2 pole breakers. There is definitely not a grounded or grounding conductor.
This was done by someone who believes a ground rod or other electrode is a ground.
I just have to decide what I'm going to do with it.

Scary situation. Definitely a hazard. Check out the IAEI article. This is apparently a wide spread problem.

 

[hurk27]

This is a long believed myth that ground rods will prevent shocks, and is still believed by some even to this day, and mostly because it is still a requirement in the NEC, there are many threads on here that prove ground rods do nothing to make anything safer, and as for lightning there is a published paper that University of Florida did a test on a structure at camp blanding that showed that they don't even protect much from lightning, it was posted here back in 2006 and if I can get the search function to work maybe I can find it, Brian I think was the one who posted it.

But it is my feelings that ground rods as an electrode should be removed from the NEC as they do not work, but people will still believe they do just because they are required, for every reason someone has to promote them, I can show proof that they will not function for that purpose or are not really needed because not far away is another electrode doing the same thing such as to prevent static buildup which would not happen with the utility bond at the transformer, a primary to secondary fault? if the bond to the MGN at the transformer doesn't open the circuit I sure hope someone don't think a ground rod will? remove touch hazard, Nada, open a OCPD, nope wont happen.

but as long as people think they will we will find dangerous installs like this.

as for a fix, a GFCI could make the install Little safer, but not dependable, bonding one side of the 240 volts only if the supply transformer is not center tap grounded already, Isolating transformer? another good possibility as it then could be grounded but using a grounded circuit conductor is still a dangerous thing as if this conductor looses connection it will still cause all the poles to be energized not a good idea which is the reason why we should never use a current carrying conductor to ground something.

So the only sure way is to run an EGC?

 

[Hv&Lv]

This was installed in 1986 and not by a utility company. It is metered and fed by 20 amp 2 pole breakers. There is definitely not a grounded or grounding conductor.
This was done by someone who believes a ground rod or other electrode is a ground.
I just have to decide what I'm going to do with it.

If it is metered then it isn't the utilities and should have fallen under the NEC IMO. We have many area lights out there that are ours and we are required to ground them per section 21 rule 215. Also in that rule, "Supply circuits shall not be designed to use the earth normally as the sole conductor for any part of the circuit."
While we aren't required to run a EGC, we generally feed all our underground area lights with either Romex^? or another wire that includes a seperate grounding couductor. It makes life easier to do it that way and avoid consumer complaints.