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  1. #1
    Paul Cobb's Avatar
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    Cool LV light shock problem.............

    A customer called me complaining of getting a small surge of electricity from the LV light trim at the deep end of his pool. He is getting a small dose of current when he gets near the trim piece. After 5 hours of troubleshooting the issue, I gave up. I opened up the pool light j-box and secured a copper conductor to the brass base and strung it along the ground to the edge of the pool. I set my fluke on 200vac and touched one lead to the wire and the other lead to the water. I got a reading of 2.3 vac. I got the same reading even after I turned off the main circuit breaker feeding the house. I performed the same check on the spa and got 0 potential. I also performed the same test on the water system of the house and still got 0 potential. The house (that was originally built in 1959)was torn to the ground 5 years ago and rebuilt and re-wired from the ground up. The pool however was kept the same. I've only been in the trade since 1978 but I seem to remember older electricians talking about how they used to drive ground rods into the middle of the pool for bonding. Everything in the entire electrical service is tight and wired properly. The service is underground in conduit to a hand hole at the bottom of the power company pole and the run is about 100 lineal feet. This is driving me nuts. I've never had a problem I couldn't solve within a few hours. I wonder if a chemical imbalance could cause a little voltage surge? Any help would be appreciated. Thanks.

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  2. #2
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    Default Re: LV light shock problem.............

    I am not an electrician but it sounds like an induced voltage gradient, the very reason for bonding all metal on the pool and equipment.
    Your pool "ground" could be influenced by the house on either side, power poll, or any number of issues. The entire pool shell, pipes, equipment, light needs to be bonded but it sounds like it is not.

    Try visiting Mike Holt's site and forum.

    Jim Luttrall
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  3. #3
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    Default Re: LV light shock problem.............

    Thanks for the feedback Jim. The main issue I have is the age of the pool and the code that was in effect in 1959 for pool bonding if there was such a requirement. If I knew that, the problem would be easier to address.


  4. #4
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    Default Re: LV light shock problem.............

    Jerry and others may be of help on the date codes became effective... but why does that make a difference?
    1. You don't know if the code was followed.
    2. Electricity doesn't care what code was in effect.
    3. The original bonding could have been perfect, but at this age it all needs to be examined since things wear out in 50 years.
    From the website: Top 2008 NEC Changes; 680.26 Equipotential Bonding for Swimming Pools, Spas and Hot Tubs




    The bonding rules for reducing voltage gradients around permanently installed pools, outdoor spas, or outdoor hot tubs were changed again. Here's a summary of the entire section.
    (A) Performance. Equipotential bonding is intended to reduce voltage gradients in the area around permanently installed pools, outdoor spas, or outdoor hot tubs by the use of a common bonding grid in accordance with 680.26(B) and (C).
    (B) Bonded Parts. The parts of a permanently installed pool, outdoor spa, or outdoor hot tub listed in (B)(1) through (B)(7) shall be bonded together with a solid copper conductor not smaller than 8 AWG with listed pressure connectors, terminal bars, exothermic welding, or other listed means [250.8(A)]. Equipotential bonding is not required to extend to or be attached to any panelboard, service equipment, or grounding electrode.
    (1) Conductive Pool, Outdoor Spa, and Outdoor Hot Tub Shells.
    (a) Structural Reinforcing Steel. Unencapsulated structural reinforcing steel secured together by steel tie wires is considered bonded.
    (2) Perimeter Surfaces. An equipotential bonding grid shall extend 3 ft horizontally beyond the inside walls of a pool, outdoor spa, or outdoor hot tub, including unpaved, paved, and poured concrete surfaces. The bonding grid shall comply with (a) or (b) and be attached to the conductive pool reinforcing steel at a minimum of four points uniformly spaced around the perimeter of the walls of a pool, outdoor spa, or outdoor hot tub.
    (a) Structural Reinforcing Steel. Structural reinforcing steel [680.26(B)(1)(a)]. Author’s Comment: The 2008 NEC does not provide any guidance on the installation requirements for structural reinforcing steel when used as a perimeter equipotential bonding grid.
    (b) Alternate Means. Equipotential bonding conductor meeting the following:
    (1) 8 AWG bare solid copper bonding conductor.
    (2) The bonding conductor shall follow the contour of the perimeter surface.
    (3) Listed splicing devices.
    (4) Bonding conductor shall be 18 to 24 in. from the inside walls of the pool.
    (5) Bonding conductor shall be secured within or under the perimeter surface 4 to 6 in. below the subgrade.
    (3) Metallic Components. Metallic parts of the pool, outdoor spa, or outdoor hot tub structure shall be bonded to the equipotential grid.
    (4) Underwater Metal Forming Shells. Metal forming shells and mounting brackets for luminaires and speakers shall be bonded to the equipotential grid.
    (5) Metal Fittings. Metal fittings sized 4 in. and larger that penetrate into the pool, outdoor spa, or outdoor hot tub structure, such as ladders and handrails shall be bonded to the equipotential grid.
    (6) Electrical Equipment. Metal parts of electrical equipment associated with the pool, outdoor spa, or outdoor hot tub water circulating system, such as water heaters, pump motors, and metal parts of pool covers shall be bonded to the equipotential grid. (see Figure)
    Exception: Metal parts of listed equipment incorporating an approved system of double insulation is not required to be bonded to the equipotential grid.
    (a) Double-Insulated Water Pump Motors. Where a double-insulated water-pump motor is installed, a solid 8 AWG copper conductor from the bonding grid shall be provided for a replacement motor.
    (b) Pool Water Heaters. Pool water heaters shall be grounded and bonded in accordance with equipment instructions.
    (7) Metal Wiring Methods and Equipment. Metal-sheathed cables and raceways, metal piping, and all fixed metal parts shall be bonded to the equipotential grid.
    Exception No. 1: Where separated from the pool, outdoor spa, or outdoor hot tub structure by a permanent barrier.
    Exception No. 2: Where located more than 5 ft horizontally of the inside walls of the pool, outdoor spa, or outdoor hot tub structure.
    Exception No. 3: Where located more than 12 ft measured vertically above the maximum water level. (C) Pool Water. A minimum conductive surface area of 9 sq in. shall be installed in contact with the pool, outdoor spa, or outdoor hot tub structure water. This water bond is permitted to consist of metal parts that are bonded in 680.26(B). Author's Comment: This section was completely rewritten to clarify equipotential bonding requirements for permanently installed pool, outdoor spa, or outdoor hot tub areas.

    Last edited by Jim Luttrall; 03-02-2009 at 10:01 PM.
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    Default Re: LV light shock problem.............

    A couple of questions:

    Is the spa an in ground or above ground fiberglass spa or is it an in-ground concrete spa? If concrete, part of, or separate from, the pool?

    Have you removed the pool light from the wet niche, looked at and measured the pool light bonding conductor's resistance? At that age, if the pool light has not already been replaced as well as the pool light cord, they could be causing the problem.

    Is the low voltage pool light GFCI protected?

    Being as you got the same reading with the power off, I'm guessing the cause is stray electrical current from the power company neutral/ground - otherwise that would have gone away when the main was turned off.

    You might be able to "eliminate the symptom" by making sure everything is bonded well, starting at the pool light.

    Have you checked for current on the grounding electrode conductor? If there is current there, that goes back to the pole via the earth. With that house's main off, that house would not have (should not have) any current, thus no stray current *from that house*, but there could be other stray currents around from the power company.

    Current on the grounding electrode conductor does not mean there is a fault, though. Think of it as a parallel electrical circuit with two conductor paths connected at each end to the same terminal, think of the neutral conductor path as a very low resistance placed in one conductor path and the earth ground as a very high resistance placed in the other conductor path - technically, that *IS* the circuit you have.

    Here is an example of the above: Put two different resistances on a lamp cord and plug the lamp cord in, being careful not to touch either resistance. One resistance will glow real bright and the other will barely glow.

    Don't believe me? Curious as to what size resistors to use? One resistor is called a 1500 watt flood lamp and the other is called a 4 watt night light. The 4 watt night light is the earth conductor path back to the transformer.

    Will *all* of the neutral current go back to the transformer through the neutral conductor? Nope.

    Will *most all* of the neutral current go back to the transformer through the neutral conductor? Yep.

    Okay, so where is *the rest* of that neutral current going back to the transformer? Through the earth ground.

    Now think of that happening at each and every house's electrical service. Could there be stray electrical currents all over? You betcha. Not only "could there be" but "there are". The only real way to solve the problem is to run the grounding electrode conductor back to the transformer instead of connecting it to earth. But ... wouldn't that have a negative effect on the grounding electrode system's ability to take a lightning strike back to earth? Again, you betcha. The classic Catch 22. Could they, then, make two separate "grounding" systems", one to handle lightning and the other to handle the electrical system's unintended currents? Yep. They are called "lightning rod systems", but for them to work totally separately the current method of grounding to earth would have to change to 'grounding to the transformer', not earth, leaving on the lightning rod system going to earth ground. Not going to happen and it would need a lot of experimenting to see what, if any, the negative aspects of doing such would have on the building electrical systems' safety - which is way beyond my capabilities. (Added with edit: One could run an equipment grounding conductor back to the transformer *and* still connect the system to ground at the building, *each additional properly sized groundED/groundING conductor run back to the transformer* will dramatically reduce the earth ground path current, thus still allowing the service to be connected back to earth at the service while dramatically reducing the stray currents.)

    As Jim said, regardless of what pool bonding was required back then, all the changes have been made to improve pool bonding to the extent that it is now - safety knows no code editions and electricity goes where it wants without reading up on what code was in effect when.

    Last edited by Jerry Peck; 03-03-2009 at 06:43 AM. Reason: added sentence at end of second to last paragraph: (Added with edit: blah, blah, blah.)
    Jerry Peck
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  6. #6
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    Default Re: LV light shock problem.............

    GFCI protection for the underwater lighting fixtures in swiming pools was one of the first NEC mandated GFCI protections for residential areas. It showed up in the 1968 edition of the NEC.

    Since you indicated in your post that this was experienced "in the deep end" near an underwater light's trim and that this was regarding a POOL,

    I think it is fair to assume that this is regarding an in-ground swimming pool.

    Since we don't know what or how many possible additions, replacements, maintenance, changes in equipment may have taken place over the years,

    Nor if there is present a proximity issue regarding other items such as low voltage landscape lighting componants, sprinkler controlls, underground cable TV entrance, Land-line telephone, etc. nor other electrical systems I would first check on the vintage and status of the GFCI protection in place.

    The "grid" has had so many changes in the requirements over the years, and a system 50 years old I wouldn't trust too many factors with old concrete, rod, under ground shifts, sink holes, water table, aquafers, etc. with the unstable earth's "crust" in so much of FL that even if everything was done as it should have been doesn't mean it is still as it should be. What may have been in contact with "earth" may no longer be there, or the "earth" itself may no longer be there.

    Personally, I would never trust one of those earlier GFCI devices. Age, technology, prior trips, etc. can render them nearly useless.

    Personally, I would never trust one of those earlier or older GFCI devices. Age, technology, prior trips, etc. can render them nearly useless.

    This is nothing to dabble with. This is something that a licensed master electrician with much experience with vintage in-ground pools should be diagnosing.

    Last edited by H.G. Watson, Sr.; 03-03-2009 at 02:47 PM. Reason: changed reference from 60's to 1968

  7. #7
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    Default Re: LV light shock problem.............

    Quote Originally Posted by Jerry Peck View Post
    A couple of questions:

    Is the spa an in ground or above ground fiberglass spa or is it an in-ground concrete spa? If concrete, part of, or separate from, the pool?

    spa? above ground?

    In-ground pool with a deep end, isn't it?

    I find it interesting the entire home was demolished "down to the ground" and rebuilt (C of O) and new service and entirety of electrical system but that nothing was done or required with a 50s in-ground electrified pool within last five years. Which county/jurisdiction is this in?

    Last edited by H.G. Watson, Sr.; 03-03-2009 at 02:59 PM.

  8. #8
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    Default Re: LV light shock problem.............

    The house is in the city of Delray Beach, Florida. The chief electrical inspector in the city is the son of the person I did my apprenticeship with many years ago. I found out on Mike Holts forums that article 680 didn't exist until 1964. This would explain the lack of eqipotential bonding grid. I am leaning toward utility related issues regarding their habit of bonding neutrals to earth in several locations around the neighborhood.


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    Default Re: LV light shock problem.............

    Quote Originally Posted by Paul Cobb View Post
    I performed the same check on the spa and got 0 potential.
    Quote Originally Posted by Jerry Peck View Post
    A couple of questions:

    Is the spa an in ground or above ground fiberglass spa or is it an in-ground concrete spa? If concrete, part of, or separate from, the pool?
    Quote Originally Posted by H.G. Watson, Sr. View Post
    spa? above ground?

    In-ground pool with a deep end, isn't it?
    Yes, "spa", see above quote from original post to find out why the question was asked.

    I find it interesting the entire home was demolished "down to the ground" and rebuilt (C of O) and new service and entirety of electrical system but that nothing was done or required with a 50s in-ground electrified pool within last five years. Which county/jurisdiction is this in?
    Yes, someone from Delray Beach really dropped that ball.

    Even if classifying the pool as a "separate structure" (which it is) and someone saying they were not doing any work on "that structure and therefore did not need to bring that structure" to current code, the response from the city should have been "No problem, and, since you are disconnecting and removing power *to that structure*, you will need a permit and need to completely bring *that structure* to current code before power will be allowed to be connected to *that structure*."

    Either way, the contractor would have had to bring the pool and its wiring, including bonding, to current code.

    Last edited by Jerry Peck; 03-03-2009 at 07:53 PM. Reason: speelin'
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    Default Re: LV light shock problem.............

    Quote Originally Posted by H.G. Watson, Sr. View Post
    GFCI protection for the underwater lighting fixtures in swiming pools was one of the first NEC mandated GFCI protections for residential areas. It showed up in the 1968 edition of the NEC.

    Actually, the 1968 NEC says "or" in reference to GFCI protection for underwater pool lights - there are two other choices other than GFCI protection.

    From the 1968 NEC.
    - 680-4. Lighting.
    - - (g) Underwater lighting fixtures supplied either directly from a branch circuit or from a transformer meeting the requirements of Section 680-4(h) shall perform reliably under any combination of likely fault conditions so that there is no shock hazard. Compliance with this requirement shall be by one of the following:
    - - - (1) The design or construction of the fixtures; or
    - - - (2) The use of a ground-fault circuit interrupter.
    - - - - (then it gives the definition of a ground-fault circuit interrupter)
    - - - (3) Other acceptable means.

    Jerry Peck
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    Default Re: LV light shock problem.............

    Well since its a LV light I think he'd need subsection (h).

    Good Luck Paul Cobb. As I said you might want to get back to the city inspectors on this issue, something not quite right about the back story.

    The ecg and isolating post panel bond from neutral wasn't followed before the 60s. Intermittant "grounds" were common as generational repairs, upgrades made until the practice was outright prohibited. IIRC the 4-wire 1~240v wasn't required until the late 90s.

    I think you may find this article helpful and mostly on point regarding bonding and ecg and gfci water areas.
    Electrical Contractor: Electrocution in a Water Fountain

    Although the particilar incident discussed is a fountain, the history regarding parts of Chapter 2. I couldn't find the particular article I thought I had saved (might be on the old computer that refuses to boot up today) specifically on an incident regarding a 50s or 60s vintage inground pool and LV underwaterline lighting. (Might have been an IAEI story from a few springs ago). If I happen across it I'll return to the string and post it.

    Hope that helps.

    H.G.

    Last edited by H.G. Watson, Sr.; 03-08-2009 at 01:49 PM.

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    Default Re: LV light shock problem.............

    "from a transformer meeting the requirements of Section 680-4(h)"

    Quote Originally Posted by H.G. Watson, Sr. View Post
    Well since its a LV light I think he'd need subsection (h).
    Subsection (h) does not require GFCI protection either, it just establishes the requirements of the transformer.

    "(h) Transformers used for the supply of fixtures, together with the transformer enclosure, shall be approved for the purpose. The transformers shall be a two-winding type having a grounded metal barrier between the primary and secondary voltage windings."

    Jerry Peck
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    Default Re: LV light shock problem.............

    Thank you for posting the reference Jerry Peck.

    And thus between (h) and the fixture gasket, and the old chapter 2
    I think we may have identified enough for Paul Cobb to work on.

    In the meantime I'll wait for Paul Cobb (except to follow up with that article link if I can find it. Coffee's worn off and its time for a nap.


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    Default Re: LV light shock problem.............

    Quote Originally Posted by H.G. Watson, Sr. View Post
    And thus between (h) and the fixture gasket, and the old chapter 2
    I think we may have identified enough for Paul Cobb to work on.

    I agree with that ... Paul definitely has more than enough to work with.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
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    Default Re: LV light shock problem.............

    Something's been haunting me about this string.

    1959 pool. Underwater lighting. Its been bugging me.

    I thought I had a lightbulb moment while preparing sandwiches today for Lunch:

    A date from a NEC code reference... (May 1st?) 1965 regarding pools constructed prior to that date requiring GFP/GFCI for underwater lighting 20 or 30 mA trigger ("Class B"). Grid/rod....... brain drain

    So I started poking around in boxes looking for old materials.

    As the coffee is wearing off and perusing old materials along with the digestive process and activity, is throwing me into the strong desire for a nap, so I'm not inclined to keep looking for it (keep nodding off struggling to read fine print).

    Anyhow...in-ground pools constructed prior to the effective date had a proviso requiring the lighting circuit be protected with a CLASS B GFCI (not class A). Thinking this included LV at or above either 12 or 15v.

    I'm (rattling skull!) thinking the reference may have later gone poof somewhere perhaps in the late 90s, but might have changed as the Class A's became more reliable (70s-90s). A reference that's that's haunting me might be burried in a disappearing exception sometime before 2002 on bonding.

    Jerry Peck, If you've got the time and the materials handy - perhaps you can focus in on it. Do you have the pre-68 handy? Might have been forecast 2 editions prior.

    IIRC the applicable pools' "birth dates" could even be slightly later in FL as to when required, but those "born" before the mid 70s.

    Might even be a reference in the muddlings of the late 80s into the 90s.

    I recall an old test ? or inspection check list - I can almost see it in my brain...where IS it????

    Last edited by H.G. Watson, Sr.; 03-10-2009 at 01:54 PM.

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    Default Re: LV light shock problem.............

    Quote Originally Posted by H.G. Watson, Sr. View Post
    Jerry Peck, If you've got the time and the materials handy - perhaps you can focus in on it. Do you have the pre-68 handy? Might have been forecast 2 editions prior.
    1968 is only mid-way through my collection.

    The earliest (first) reference to underwater lighting (swimming pools) is in the 1962 NEC. In fact, that is when Article 680 was first put into the code - in 1962.

    From the 1962 NEC.
    - 680-4 Lighting.
    - - (a) The provisions of the Section apply to lighting fixtures installed below the pool surface.
    - - (b) No lighting fixtures shall be installed for operation at more than 150 volts.
    - - (c) A nonmetallic fixture shall not be used with a grounded power supply.
    - - (d) All noncurrent carrying metal parts of lighting fixtures shall be grounded whether exposed or enclosed in nonconducting materials.
    - - (e) Fixtures approved for the purpose may be installed outside the walls of the pool in closed recesses which are adequately drained and accessible for maintenance.
    - - (f) Approved metal fixture housings (forming shells) shall be installed for the mounting of all underwater fixtures and shall be equipped with provisions for conduit entries. Metal parts of the fixture, fixture housing, and the supply conduit below grade level shall be of brass or other suitable copper alloy. The conduit shall extend from the fixture housing (forming shell) to a suitable junction box located as provided in Section 680-5 of this Article.
    - - (g) All circuits supplying underwater fixtures should be isolated. If the circuit voltage is greater than 30 volts, an approved fail-safe ground detector device which automatically de-energizes the circuit or an approved grid structure or similar safeguard should be used.
    - (h) Transformers used for the supply of fixtures, together with the transformer enclosure, shall be approved for the purpose. The transformers shall be of an isolating type having a grounded metal barrier between the primary and secondary voltage windings.

    Note that in (g) there are four choices:
    - - (g) All circuits supplying underwater fixtures should be isolated.
    - - - If the circuit voltage is greater than 30 volts,
    - - - and approved fail-safe ground detector device which automatically de-energizes the circuit
    - - - or an approved grid structure
    - - - or similar safeguard should be used.

    The first choice is to use a transformer operating at less then 30 volts.

    The second choice is to not use a transformer operating at less than 30 volts but with a circuit operating at less than 150 volts, with three options for protection, one of which is the fore-bearer to what is now called the 'ground-fault circuit interrupter'.

    Jerry Peck
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    Default Re: LV light shock problem.............

    Thank you Jerry Peck.

    Since you have it handy can you check the bonding and grounding requirements in Chapter 2 for 1962 and a prior edition before the introduction of section 680? and the one in between. If you might also take a gander on when there was a change to 15v+

    I just flew a circuit and whew! my arms are tired! (actually everything is tired, brain, body and spirit)

    That date 1965 and the merry month of May for pool's construction date is haunting me still. Might be a Bonding or grounding reference. I'm fairly certain it is burried somewhere either back then or later with a retroactive requirement.


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    Default Re: LV light shock problem.............

    In 1962 680-7 Grounding, began addressing bonding as we know it today only under the term "grounding".

    Prior to that, in the 1959 NEC, 250-G Bonding, did not address pools are anything like them.

    Jerry Peck
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    Smile Re: LV light shock problem.............

    Paul Cobb,

    I see now your location is South Florida however I had previously thought your displayed location was Delray Beach Florida. I could be remembering incorrectly.

    Anyway, the edition regarding substantial changes in pool construction was not 1959 or 1962 as another poster suggests, but the 1965 NEC.

    The next major change on these issues (substantial) is 1996.

    If you refer to your handbook notes you will find commentary similar to the following:

    (Handbook): A ground-fault circuit interrupter is intended to be used only in a circuit that has a solidly grounded conductor; however, an equipment grounding conductor is not necessary in order for the GFCI to function. A Class A GFCI trips where the current to ground has a value in the range of 4 through 6 mA; it is suitable for use in swimming pool circuits. It should be noted, however, that circuits supplying pool equipment that were installed before local adoption of the 1965 edition of the Code may have sufficient leakage current to cause a Class A GFCI to trip. A Class B GFCI trips if the current to ground exceeds 20 mA; it is suitable for use only with underwater swimming pool lighting fixtures installed before the local adoption of the 1965 Code. For more information see NEC 210.8 Ground-Fault Circuit-Interrupter Protection for Personnel. and Handbook Exhibits 210.7 through 210.15. Also, see 215.9 & 215.10. Furthermore UL UL 943, Standard for Ground-Fault Circuit Interrupters.
    The topic of the post was leakage current from the LV wet-niche lighting in the deep end of the in ground pool.

    Mr. Paul Cobb was encountering objectional current and was seeking assistance and background in his investigation as to the source and a means to resolve it.

    The differences in pre- and post-1965 NEC edition adoption construction are significant.

    Additional informative articles which may be helpful:

    AFCI
    "Mismatching wet-niche swimming pool luminaires with forming shells can be a Shocking Combination". (Goes into further details identifiying objectional current.) July/Aug 2003 IAEI News.

    http://www.ul.com/global/eng/documen...impool0803.pdf

    Low-Voltage Lighting Systems Operating at 30 Volts or Less Mark Ode.
    November-December 2004 IAEI News
    http://www.ul.com/global/eng/documen...LVLighting.pdf

    Hence the haunting of the (approximate May 1st) 1965 reference in regards to your having mentioned a 1959 constructed in-ground pool. It was the 1965 edition of the NEC as corrected which was "the itch (my brain) couldn't scratch. IIRC a bulletin regarding corrections (errata post type-setting of the original printing) may have been dated May 1st for the 1965 NEC. Back "in the day" we had to manually correct our books.

    Not sure if my remembering your location as having previously been more specific is correct or if the Delray Beach area is what was "haunting me" regarding several older electrician and lay death investigations from the past.

    Any "grandfather" provisons should have been suspended when the original service and supply was eliminated along with the destruction of the orginal structure.

    Last edited by H.G. Watson, Sr.; 03-17-2009 at 08:11 AM. Reason: rats! hit submit instead of preview wanted to highlight something!

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    Default Re: LV light shock problem.............

    (sigh)

    Get it right Watson.

    You still have not admitted you were incorrect.

    (underlining is mine)
    Quote Originally Posted by Jerry Peck View Post
    The earliest (first) reference to underwater lighting (swimming pools) is in the 1962 NEC. In fact, that is when Article 680 was first put into the code - in 1962.

    From the 1962 NEC.
    - 680-4 Lighting.
    - - (a) The provisions of the Section apply to lighting fixtures installed below the pool surface.
    - - (b) No lighting fixtures shall be installed for operation at more than 150 volts.
    - - (c) A nonmetallic fixture shall not be used with a grounded power supply.
    - - (d) All noncurrent carrying metal parts of lighting fixtures shall be grounded whether exposed or enclosed in nonconducting materials.
    - - (e) Fixtures approved for the purpose may be installed outside the walls of the pool in closed recesses which are adequately drained and accessible for maintenance.
    - - (f) Approved metal fixture housings (forming shells) shall be installed for the mounting of all underwater fixtures and shall be equipped with provisions for conduit entries. Metal parts of the fixture, fixture housing, and the supply conduit below grade level shall be of brass or other suitable copper alloy. The conduit shall extend from the fixture housing (forming shell) to a suitable junction box located as provided in Section 680-5 of this Article.
    - - (g) All circuits supplying underwater fixtures should be isolated. If the circuit voltage is greater than 30 volts, an approved fail-safe ground detector device which automatically de-energizes the circuit or an approved grid structure or similar safeguard should be used.
    - (h) Transformers used for the supply of fixtures, together with the transformer enclosure, shall be approved for the purpose. The transformers shall be of an isolating type having a grounded metal barrier between the primary and secondary voltage windings.

    Note that in (g) there are four choices:
    - - (g) All circuits supplying underwater fixtures should be isolated.
    - - - If the circuit voltage is greater than 30 volts,
    - - - and approved fail-safe ground detector device which automatically de-energizes the circuit
    - - - or an approved grid structure
    - - - or similar safeguard should be used.
    (underlining is mine)
    Quote Originally Posted by H.G. Watson, Sr. View Post
    Anyway, the edition regarding substantial changes in pool construction was not 1959 or 1962 as another poster suggests, but the 1965 NEC.
    Watson,

    "The other poster", being me, stated the first occurrence of pools coming into the NEC, not substantial changes. You cannot seem to admit you were incorrect, so you try to change everything to make it seem like you were correct.

    The above stated, the *FIRST* "SUBSTANTIAL CHANGES" regarding pools was ... drum roll ... 1962 ... *NOT* 1965 as you suggest.

    The previous 1959 NEC did not have any pool requirements, the 1962 NEC has a brand spanking new Article 680 for pools - if that is not a "significant change", then nothing which came after was "significant" either.

    The truth, Watson, that is all we ask, by upright, upstanding, truthful, an admit when you are wrong instead of going back and editing and changing posts to try to reflect that you were not wrong. That shows lack of personal ethics and honesty.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  21. #21
    Join Date
    Jul 2008
    Location
    Snowbird (this means I'm retired and migrate between locations), FL/MI
    Posts
    4,086

    Default Re: LV light shock problem.............

    N/A to the jurisdictional history, so what's your point?

    Made an edit before your post, so what's your point?

    You've used the edit feature, I changed nothing other than formatting, so what's your point?

    I figured out what was "haunting me" about the 1965 date I mentioned so I shared...so what's your point?

    The stealthy stalking behavior is most unbecomming, is it supposed to be flattering?

    Upset I made the observation that the pool should have been brought to code with the destruction/rebuild of the service and entire from foundation-up of the residence five+ years ago first?

    Seems to be your modus...


  22. #22
    Join Date
    Mar 2007
    Location
    Fuquay Varina, NC
    Posts
    1,074

    Default Re: LV light shock problem.............

    Ding.....Ding............

    Mike Schulz License 393
    Affordable Home Inspections
    www.houseinspections.com

  23. #23
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,042

    Default Re: LV light shock problem.............

    Quote Originally Posted by H.G. Watson, Sr. View Post
    The stealthy stalking behavior is most unbecomming, is it supposed to be flattering?

    Nothing stealthy and nothing stalking, other than your behaviour of going back and changing incorrect information to look correct and not acknowledge that you were incorrect.

    Now THAT is stealthy.

    As to the stalking part, that is you responding to virtually every post I've been making, and, of course, I return the favor as I am watching the teacher in action.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

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