Shock hazard - What would you do to correct it ?

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goldstar said:
“Just thought I'd post an update on this project. We corrected the problem on wednesday.”

“Long story - short, all splices were re-made, the neutral bar is now floating and the problem was corrected. I left the 2 ground rods in place but removed the bonding to the fence.”

“we changed it this week to current standards.”

“It does have OC protection at the source. Both insulated conductors of the triplex are hot and the EGC (messinger cable) to the second light pole was spliced to the neutral at the first light pole. I had to use that as the neutral at the light pole where 120/240 is being utilized. It was run down the pole in PVC and was too short to get extended to the EG bar that I installed in the breaker panel. So, I inserted a piece of NM seal-tight over the bare messinger up through the threaded hub so it wouldn't ground to the metal enclosure and used the #12 THHN that was wrapped around the triplex as the EGC. I know it seems like a Rube Goldberg but that's what I had t work with.”
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goldstar said:
“we changed it this week to current standards.”
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Are you sure that you changed this installations to current standards (code).
 
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kwired said:
Yes before 2005NEC (correct me if that is wrong, may have been 2008) you didn't have to run a grounded and equipment grounding conductor with the feeder to separate structures.

But if you were running a circuit to a series of lighting poles that also meant you needed a disconnecting means (that was suitable for use as service equipment), and a grounding electrode system at each pole (separate structure). If you were running a branch circuit instead of a feeder to this string of poles then you still needed separate grounded and equipment grounding conductors. Also keep in mind a branch circuit supplying lighting has a limitation of 50 amps, so if the feeder is more then that you still need branch circuit protection placed where you can limit the branch to 50 amps or less.
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Some interesting points. Not sure what was Code and when but this is what's existing. There are a total of (5) light poles. Three of the poles have a total of (6) 400 watt metal halide light fixtures running on 208 volts and the other two have (6) HPS light fixtures running on 120 volts. There were no local grounding electrode systems installed at any of the poles other than the one I installed at one of the poles serving the HPS lights. Service to the poles is fed from a 2-pole, 100 amp breaker in the main panel. Total distance of the run is about 200'. There is no local disconnect means at the poles serving the metal halide fixtures. The only local disconnect means is on the pole serving the HPS fixtures. (BTW, in case I didn't mention these are std. wooden utility poles).
 
david said:
You had a neutral and possibly an equipment ground originating at the club house from a 120/208 circuit feeding both the basket ball court then on to the volley ball court.

You discovered through your repairs at some point in those 15 years since the 208 3 phase service was added to the club house that the neutral was severed for the 120/208 circuit to the basket ball circuit, or perhaps it was never connected to begin with.

You had a 120/240 volt service originating from the utility pole (owners property) at the volley ball court.

The 120/240 volt service line one and line two where disconnected from the utility pole and the club house at the time the 208 3 phase service took its place 15 years ago during that remodel.

The messenger neutral from the 120/240 volt service was still intact until the tree came down and you where called to investigate a shock hazard.
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You know what I am going to go to bed thinking about?

Before the tree fell and disconnected the neutral from the utilities single phase 120/240 volt transformer on the end of the property by the volley ball court. And since the neutral and equipment ground feeding the 208 circuit was severed from the utilities three phase service and transformer bank.

The 208 three phase A and B for example from a different transformer bank than the utilities single phase transformer was using the utilities single phase neutral to supply the four circuit panel out by the volley ball court.
 
goldstar said:
Some interesting points. Not sure what was Code and when but this is what's existing. There are a total of (5) light poles. Three of the poles have a total of (6) 400 watt metal halide light fixtures running on 208 volts and the other two have (6) HPS light fixtures running on 120 volts. There were no local grounding electrode systems installed at any of the poles other than the one I installed at one of the poles serving the HPS lights. Service to the poles is fed from a 2-pole, 100 amp breaker in the main panel. Total distance of the run is about 200'. There is no local disconnect means at the poles serving the metal halide fixtures. The only local disconnect means is on the pole serving the HPS fixtures. (BTW, in case I didn't mention these are std. wooden utility poles).
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Seems to me there is enough load that it must be divided into more then one branch circuit. The three poles with MH fixtures is getting near all a 50 amp circuit can handle - unless all three phases are supplied to them and load is balanced.

210.23(D) limits circuits supplying lighting outlets to a maximum of 50 amps.

If the pole serving the HPS fixtures was added later on - maybe whoever did that sort of knew the rules and is why they put the disconnect there (assuming it contains overcurrent protection anyway).
 
david said:
Are you sure that you changed this installations to current standards (code).
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Did I change the entire installation to current standards ? No. Did I re-splice the existing wiring to what it was before the tree came down ? Yes Did I bring the wiring to the light pole utilizing 120 volts up to the current Code ? I believe I did. Would an EI pass this entire installation ? Probably not. Did I make the installation safer than what it was ? I believe I did. Short of ripping the entire installation out and starting anew to the tune of about $10K I don't know how else to answer your question.
 
kwired said:
Seems to me there is enough load that it must be divided into more then one branch circuit. The three poles with MH fixtures is getting near all a 50 amp circuit can handle - unless all three phases are supplied to them and load is balanced.

210.23(D) limits circuits supplying lighting outlets to a maximum of 50 amps.
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I understand that now but there is no over-current protection at the poles where MH fixtures are installed. Just to clarify, the supply voltage to the club house is 120/208 VAC, 3 phase. The supply to the light poles is 120/208 VAC, single phase and is supplied via a 100 amp, 2-pole circuit breaker.
If the pole serving the HPS fixtures was added later on - maybe whoever did that sort of knew the rules and is why they put the disconnect there (assuming it contains overcurrent protection anyway).
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Maybe so. There are (4) 20 amp circuit breakers in that panel.
 
goldstar said:
Did I change the entire installation to current standards ? No. Did I re-splice the existing wiring to what it was before the tree came down ? Yes Did I bring the wiring to the light pole utilizing 120 volts up to the current Code ? I believe I did. Would an EI pass this entire installation ? Probably not. Did I make the installation safer than what it was ? I believe I did. Short of ripping the entire installation out and starting anew to the tune of about $10K I don't know how else to answer your question.
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With any existing installation we all have to ask the question "Where do I stop?".
Sometimes it is pretty obvious, others you do what you can. You may want to CYA, and suggest future work would be required to make the installation code compliant. You fixed the immediate threat.
 
goldstar said:
Thanks, I did just that. Not sure if it really absolves me of any liabilities or not.:?
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Maybe not entirely, but good documentation of this will show that those that make decisions were aware there may be some problems and puts more liability on them.
 
goldstar said:
No. Did I re-splice the existing wiring to what it was before the tree came down ? Yes Did I bring the wiring to the light pole utilizing 120 volts up to the current Code ? I believe I did.
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See this is one area I think needs clarified, I cannot see what you have described in this discussion, but if I understand correctly what you are seeing.

Than before the tree came down the 208/120volt panel at the volleyball court was originally supplied by 120/240 volt single phase. which you said was disconnected from the utility and from the club house when the service at this facility was change from 120/240 single phase to 120/208 three phase.

You never clarified if the messenger supported nuetral from the original 120/240 single phase was left connected to the utility. I suspected that it was since this system lost it nuetral when the tree came down and also because you indicated that the nuetral from the club house 120/208 supply was discovered to be severed while you where doing your repairs.

You indicate here you re-spiced the existing wiring to what it was before the tree came down. If so it should be insured that the messenger supported nuetral from the volleyball utility pole needs disconnected from the utilities 120/240 system. If not you will have a connection to the utilities nuetral from both the volleyball court end and the clubhouse end.

Edit: Assuming that the 120/208 three phase service is originating at the club house end of this facility
 
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Shock Hazard

Shock Hazard

I have not read all of the posts here but to simplify it in my mind, are we to assume that the shock hazard was caused by the flow of current thru the ground wire (and fence) back to the supply transformer as a result of the improper neutral-ground connection that he found?
 
david said:
See this is one area I think needs clarified, I cannot see what you have described in this discussion, but if I understand correctly what you are seeing.

Than before the tree came down the 208/120volt panel at the volleyball court was originally supplied by 120/240 volt single phase. which you said was disconnected from the utility and from the club house when the service at this facility was change from 120/240 single phase to 120/208 three phase.

You never clarified if the messenger supported nuetral from the original 120/240 single phase was left connected to the utility. I suspected that it was since this system lost it nuetral when the tree came down and also because you indicated that the nuetral from the club house 120/208 supply was discovered to be severed while you where doing your repairs.

You indicate here you re-spiced the existing wiring to what it was before the tree came down. If so it should be insured that the messenger supported nuetral from the volleyball utility pole needs disconnected from the utilities 120/240 system. If not you will have a connection to the utilities nuetral from both the volleyball court end and the clubhouse end.

Edit: Assuming that the 120/208 three phase service is originating at the club house end of this facility
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Let me see if I can explain this so we're all on the same page and let's start from the assumption that the tree hasn't come down yet and severed anything.
  • The old service to the clubhouse was 120/240 VAC
  • That service was abandoned and although disconnected at the utility pole in the street was left in tact to the clubhouse via a separate utility pole on the premises
  • The new service to the clubhouse is a 120/208, 3-phase service
  • Power to the light poles is single phase 120/208 (4 wires) via a 100 amp, 2-pole circuit breaker
  • Although 120/208 VAC single phase was run to the first light pole (with 4 MH fixtures) those fixtures ran on only 208 VAC
  • When the power was run to the light poles that required 120 volts it was originally run with tri-plex but I'm guessing that someone with a little knowledge realized that a neutral was required at that pole so they wrapped a piece of # 12 THHN around the triplex.
  • When they got to that pole I'm guessing (again) that they had extra triplex and used that to run down to the breaker panel on the pole
  • The shock hazard occurred because both the neutral and messenger were disconnected at the first light pole when the tree came down. Although the breaker panel on the 120 volt pole had a floating neutral bar it was bonded to the enclosure with the bonding screw. There was no ground run down through the PVC into the panel but there was a neutral at the top of the utility pole. The messenger was landed on the neutral bar and was touching the metal hub at the entry
  • Seeing as how the lighting load at the 120/208 volt pole was minimal we decided to splice the neutral at the first pole to the # 12 THHN. When we got to the light pole that required 120 VAC we spliced the 12 THHN neutral to the messenger of the tri-plex going down through the PVC to the breaker panel but reused the actual original messenger and fed to the last light pole that required 208 VAC.
Whew !!! Hope that makes it clear.
 
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