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Posted By: Yoopersup Static Line as Grounding conductor - 10/13/11 06:54 PM
Can a Static Line be used to Ground HV (4160 0r 13.8 Impedience grounded systems between buildings on poles??
I think your either required to have a Neutral or Grounding conductor.
Yoopersup
Posted By: George Little Re: Static Line as Grounding conductor - 10/19/11 10:04 PM
Ernie— I don't see anyone responding to your question and I think that possibly they don't understand the question or some of the terms you are using. I've been in the trade for 45+ years and I thought I understood quite a bit about code and I don't know what you are asking. Hope I'm not the only one. Maybe you could either elaborate or re-word the question or give us more details.

See Ya at the EAB meeting on the 3rd.
Posted By: gfretwell Re: Static Line as Grounding conductor - 10/20/11 07:56 AM
I was waiting for an explanation too. My guess is "static line" refers to the bare messenger and that is usually also the neutral but I could easily be wrong.

My experience looking at FPL is they use the grounded conductor on top for high voltage transmission lines and it is on the bottom for medium voltage distribution, below the 120/240.
Posted By: HotLine1 Re: Static Line as Grounding conductor - 10/20/11 01:24 PM
I sent Yoop a PM the day he posted this asking for some additional info. My thoughts went toward some type of 'mining' equipment.

Posted By: Yoopersup Re: Static Line as Grounding conductor - 10/20/11 06:13 PM
Static Line : Definition
A Grounded wire at the Very top of the Pole intended to protect lower conductors from lighting.
Impedience Grounding is grounding thur a Neutral Ground Resister.(Limits fault current to ground) see 250.186.
My Question : Static line can it be used as a grounding conductor as 250.4 (A) 5 requires.
I Know it can't be used as a Neutral.But as a Ground??
Its refered as a Static line on the prints.
This apply to a 13.8 & a 4.16 over head & underground Customer owned Feeder.
Posted By: HotLine1 Re: Static Line as Grounding conductor - 10/20/11 07:29 PM
Yoop:

Some quick research brought this up...

250.184 Solidly Grounded Neutral Systems.
Solidly grounded neutral systems shall be permitted to be either single point grounded or multigrounded neutral.
""For systems over 1000 volts, the Code permits solidly grounded neutral systems that are either single-point grounded or multigrounded systems. For the 2005 Code, 250.184 was reorganized, and new requirements for the installation of single-point grounded systems were added. Circuits supplied from a single-point grounded system are required to have an equipment grounding conductor run with the circuit conductors, and this conductor is not to be used as a conductor for continuous line-to-neutral load.""

Text within the double quotes ("") is commentary from 2008 NEC Handbook.

Posted By: Yoopersup Re: Static Line as Grounding conductor - 10/20/11 09:31 PM
This is an Impedance grounded system not solidly grounded.
Yoopersup
Posted By: Tesla Re: Static Line as Grounding conductor - 10/20/11 10:05 PM
I wouldn't dream of tapping into any conductor that is designed to ATTRACT lightning.

Sure, it'd work okay most of the time...

Then, blammo, lightning races across your grounding grid at the speed of light.

Posted By: ampherder Re: Static Line as Grounding conductor - 10/20/11 11:04 PM
Speed of light?
Posted By: gfretwell Re: Static Line as Grounding conductor - 10/21/11 12:04 AM
The only reason I question that logic is FPL puts the ungrounded conductor on the top of the pole in MV distribution. (and this is Florida where we have a lot of lightning)
Posted By: Yoopersup Re: Static Line as Grounding conductor - 10/31/11 09:47 PM
Explain myself a bit better,
4160 & 13.8 Y sysyems Impedance (NGR) grounded Systems.
Start off underground 3 phases & Ground from equipment.
Then hit a pole Line go up pole Ground wire ties to Static Line runs lenght of pole line.
Drops back down to Ductbank ties back into 3 phases & ground wire.
Static line Grounded to ground rod at each pole.
CAN a static line be used for this Purpose????
This is all Feeders Owners Equipment.
Yoopersup
I miss anything??
Posted By: HotLine1 Re: Static Line as Grounding conductor - 11/01/11 01:01 AM
Yoop:

As I understand your question, IMHO, as long as the AWG of the 'static line' is compliant with the OCP, I see no reasoning why you can't use it. It is NOT a neutral.

Text from what I believe is the relevant Article (2011)
"250.186 Impedance Grounded Neutral Systems. Impedance
grounded neutral systems in which a grounding impedance,
usually a resistor, limits the ground-fault current
shall be permitted where all of the following conditions are
met:
(1) The conditions of maintenance and supervision ensure
that only qualified persons service the installation.
(2) Ground detectors are installed on the system.
(3) Line-to-neutral loads are not served.
Impedance grounded neutral systems shall comply with
the provisions of 250.186(A) through (D).
(A) Location. The grounding impedance shall be inserted
in the grounding electrode conductor between the grounding
electrode of the supply system and the neutral point of
the supply transformer or generator.
(B) Identified and Insulated. The neutral conductor of an
impedance grounded neutral system shall be identified, as
well as fully insulated with the same insulation as the phase
conductors.
(C) System Neutral Conductor Connection. The system
neutral conductor shall not be connected to ground, except
through the neutral grounding impedance.
(D) Equipment Grounding Conductors. Equipment
grounding conductors shall be permitted to be bare and
shall be electrically connected to the ground bus and
grounding electrode conductor.
Posted By: Yoopersup Re: Static Line as Grounding conductor - 11/01/11 10:48 PM
Back to Question:
Can a Static Line Be used as A equipment Grounding conductor????
Remember on prints its noted as a STATIC Conductor.
Not a Equipment grounding conductor.
Might be OK I'd just like to see where thats Stated.
Yoopersup
(Thanks for all the imput)
Posted By: HotLine1 Re: Static Line as Grounding conductor - 11/02/11 12:23 AM
Yoop:

I did a quick search in the '08 handbook (CD) and got zero hits on static line. You (us) may have to dig into the NESC for this one. As I said above, I see no reason you can't use it as of now.

Posted By: Yoopersup Re: Static Line as Grounding conductor - 11/02/11 10:44 PM
Theres different Definations for a Satic line & an Equipment Equipment grounding conductor.
Neither refers to the other.
The NEC is behind in the High Voltage Area.
Then throw in that its an Impeadence Grounding System.
That makes it even more interesting.
If you come up with anything conrete let me know John .
Yoopersup
Posted By: HotLine1 Re: Static Line as Grounding conductor - 11/03/11 12:56 AM
Yoop:

Have you looked thru the 2011 NEC, or the NESC?

I have NESC at work, time permitting tommorrow.....

'11 is in my car, maybe reading materials tonite.

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