We are having yet another NEC disagreement in the City of Tampa. I say 680.10 and Table 680.10 are depths for conduits containing wiring not associated with the pool.
I first base my opinion on the Handbook statement; “This section allows wiring within 5 ft of the inside walls of the swimming pool under two conditions. The first condition permits wiring to pool-associated equipment such as an underwater luminaire. The second condition permits wiring not associated with the pool within this area where spatial (space) constraints such as property lines preclude the 5-ft minimum separation. Under the second condition, underground wiring located within the 5-ft zone is required to be installed in rigid metal conduit, intermediate metal conduit, or rigid nonmetallic conduit and must be buried to a depth not less than that required by Table 680.10 for these permitted wiring methods. The raceway must be installed as a complete system between points of termination and cannot simply be a sleeve through the 5-ft zone. Beyond the 5-ft zone, the minimum cover requirements of Table 300.5 apply to the underground wiring methods used for circuits rated 600 volts and less.”
The commentary specifically says the “under the second condition”, wiring not associated must be buried not less than that required by Table 680.10, pretty cut and dry to me.
The Handbook further states; “As indicated by the title of this section (Underground Wiring Location), the focus of 680.10 is to mitigate shock hazards that may occur as a result of a faulty or damaged underground installation that is in close proximity to the swimming pool. Due to water splashing out of the pool and water dripping off those who have been in the pool, the area within 5 ft of the inside walls is generally the wettest location; as a result, electrical leakage from underground installations presents a greater shock hazard in this continuously wet environment.”
So is not the interior of the PVC raceway from the pool niche also a continuously wet environment?
We install the equipotential bond ring between 18” and 24” from waters edge, would not this #8 equipotential ring dissipate any stray voltage from the underground wiring, especially the 15 volt pool light supply?

Please let me know how you all are looking at the requirements in 680.10.

Thank you,
Neal Burdick
City of Tampa Construction Inspector II

One big difference is the circuit feeding the underwater light needs to be GFCI protected. That is not necessarily true of any other system piped through the area that is not part of the pool.

What this is really saying is you can't run that UF circuit, going out in the yard, within 5' of the pool. Makes good sense to me.

Neil ; I do agree, except with the last statement about the ground ring, not especially the pool light, but including the pool light

The burial depth of the underwater light conduit is not really relevant to stray voltage in the ground. It is flooded with pool water up to the water line. That is why we have to mount the J box up in the air. Any leakage is supposed to trip the GFCI

I do not beleive that a 15 volt pool luminaire is required to be GFCI protected.
A pool luminaire over 15 volts and less than 150 volts is only required to be GFCI protected for re-lamping see 680.23(B), but everyone uses GFCI protection on anything higher than 15 volts.
I agree the conduit if always full of water, but the bond ring is there to dissipate any and all stray voltages and or currents that maybe present.

IMHO
Neal Burdick

Neal,

Please see my email response to you regarding the equipotentail bonding system.

We all need to be clear on its purpose...

Bryan,
I agree with you that the bond ring establishes an equal potential plane, but I feel it provides more protection than we realize.
From the 2008 Handbook.
"It is important to understand the difference between the terms bonding and grounding as they apply to Article 680. As defined in Article 100, bonding is “connected to establish electrical continuity and conductivity.” As described in 680.26(A), the function of equipotential bonding differs from the primary function of bonding to meet the requirements of Article 250 in that providing a path for ground-fault current is not the function of the equipotential bonding grid and associated bonding conductors.(we agree it does not provide a "ground fault" path)
The primary purpose of bonding in and around swimming pools is to ensure that voltage gradients in the pool area are not present. (what happens if there are voltage gradients present?)Section 680.26(B) specifies that the 8 AWG conductor's only function is equipotential bonding to eliminate the voltage gradient (to eliminate a voltage gradient does not a voltage gradient of some degree need to be present?)in the pool area and the bonding conductor is not required to extend or connect to any parts or equipment other than those covered in 680.26(B)(1) through (B)(7) and to a pool water bonding element covered in 680.26(C)(this is why I feel it would dissipate a voltage gradient or stray current, maybe not eliminate them completely or cause an overcurrent device to trip, but still would reduce the gradient).
The reason for electrically connecting all of the metal parts described in 680.26(B)(1) through (7) is to ensure that they all are at the same electrical potential. This bonding reduces possible injurious or disabling shock hazards created by stray currents in the ground or piping connected to the swimming pool. Stray currents can also exist in nonmetallic piping because of the low resistivity of chlorinated water." (the bond ring reduces shock possibility created by stray currents, how? I say by dissipation thru a lower resistant path).

IMHO
Neal Burdick
City of Tampa
Construction Inspector II

No, you're still a little off.

The voltage gradients are created by the pool, not by a remote voltage source.

For example, if you install an aluminum frame pool cage on the concrete pool deck that is within 5' of the pool water it needs to be bonded. WHY? Not because it may become energized by stray voltage from an electrical circuit, but due to the fact that a difference in potential can be present between the water and the pool cage. The bonding shorts out this potential.

Stray voltages from a remote source can and will energize the bonded pool parts. The equipotential bonding grid doesn't and can't mitigate that. All the parts bonded together will be energized to that potential until that source is disconnected or the reason for the stray currents is corrected.

Like I stated in my email, think of the pool and its parts like a big battery. All the exposed metal parts that can be touched are like the two electrodes. A voltage potential will be present between these metal parts. A human becomes the circuit connecting the battery, allowing current to flow. Like with a battery, the votlage comes from the battery not from a remote source.

I will be presenting a grounding and bonding class at the July ECF meeting in Tampa. This will not be your typical code based grounding and bonding class.

In this class, I will:

Explain the 3 types of bonding described in the NEC and how they are 3 completely different concepts totaly unrelated.

Explain the 2 ways the term grounding is used in the code that are 2 completely different concpets totaly unrelated.

And most importanly, explain the WHY grounding, bonding, and equipotential bonding is performed.

Yes I am a little off. LOL
I am looking forward to attending your class in July.
Wes says it is very educational, so for now we can agree to disagree.

Neal

Just think of a bird on a wire.

Here's one for you.

If equipotential bonding is a fix for stray currents, then why isn't equipotnetial bonding an option in Section 250.6 or required by any other section of Article 250?

Also, a pool is not required to have electrical equipment at all. You can install a pool in the middle of an open field in the middle of nowhere, and you would still have to install an equipotential bonding grid. WHY? Because the voltage is created by the pool, not from a remote source.

The same would apply to agricultural buildings with livestock. The voltage gradient is produced by the portential between the steel re-enforced concrete and metal parts of the building. The cow becomes the circuit. The equipotential bonding required Article 547 is mandatory whether or not a premise wiring system is present at the building or not.

Bryan, I completely agree with your take on the equipotnetial bonding requirment but I have to ask where is it mandatory that this be installed where there is no electrical? ART. 547?

John,

It is because the grid is for stray voltages and as we know cattle have a natural tendency to stray - ha ha ha ha

No seriously, though.

The telluric currents are going to get you LOL

680.26 - All the parts in (B)(1) - (7) and (C) must be bonded together. there is nothing in this section or anywhere else in the code that states that 680.26 rules are expempt to a non-electric pool.


So for example. Let's say someone builds a concrete pool, with a concrete deck, and has metal handrials. This pool is located in the middle of field with no other building within 10 miles. There is no electric serving the property or supplying the pool.

Does 680.26 still apply? YES! You still need to bond the shell, perimeter surfaces, metal rails and cups, and the pool water together. WHY? Becuase voltage grdients will be produced by the pool materials and not some other remote source.

LOL!!! Falling out of my chair. That's a good one.

Back in the day when I was a contractor. I never could see this as a issue until I wired the mile long pool in Hillsborough. Today I guess they call them river pools.
The site was still on a saw pole so the service was not energized.
As we started to connect the #8 bond to each of the 15 or so pumps.
You would see a small arc. It was a little dark in the room(no power).
When I connected the first one I was startled to see the spark. Thinking something wrong here I checked it with my fluke. I don't remember the voltage but I do remember that there was some minor voltage there compared to the ground. Not 120volts but still very high So I thought temporary power was connected to the service. And it was hosed up.
But no.
Since then I am convinced it it is a necessary item.

In fact Neal way back when in tampa when red tag baggot was around. he he!! On commercial pools. If it had a metal fence around the pool it was bonded even if it was 30 foot away from the pool edge. He required each fence post to be bonded. Let me tell you adding 30 to 50 2" jweaver clamps besides the extra #8 was not in the job cost.

All I asked was if you all were enforcing 680.10 on PVC associated with the pool.
And I think Bryan, Nick, Paul C, and Paul N all say 680.10 applies to other counduts less than 5' outside edge of pool, but we are so off topic I cannot tell.

I guess we just cannot help ourselves.
Bryan, would not a #2 "ground ring" installed as part of the grounding electrode system be the same as the #8 around a pool(which is required by the code, but no one enforces)?
There is also big difference between Equipotential Bonding in 680 and the Equipotential Plane required in 547. I agree that a bond ring is required at items covered by 680 whether or not it has electric service. From Article 680 in the 2008 Handbook "The installations covered by this article can be indoors or outdoors, permanent or storable, and may or may not be directly supplied by electrical circuits of any nature".
But Article 547 differs;
The Equipotential Plane is only required in confinement areas with concrete floors where metallic equipment is located that may become energized and is accessible to livestock.
This plane is only required where metallic equipment may become energized, so I would say it would have to have electrical service to become energized.
This #8 must be connected to the electrical grounding system (which differs from 680)to prevent a difference in voltage from developing within the plane.
So I have to ask if voltage is developed in the Equipotential Plane installed under 547 where would the voltage go?

IMHO
Neal Burdick
City of Tampa
Construction Inspector II

Hey there Y'all,

This is certainly an interesting topic. As a matter of general information, when setting up the field equations for voltage gradients about a swimming pool, one must also include a formula contribution for "voltage gradients in open air." So it would seem that Mr. Sasso's comment along with picture about the bird on a wire, really does have some relevance to the subject.

Dick Widera
Secretary, Suncoast Division IAEI

No. The purpose and function of the grounding electrode system is completely different than the purpose of the equipotential bonding grid.

The purpose of "grounding" is identified in section 250.4(A)(1), wheras the purpose of the equipotential bond is identified in Section 680.26(A). So you may be asking, what is the difference?

Grounding is to limit the voltage imposed on the premise wiring system from an EXTERNAL SOURCE, with lightning being the primary contributor. Euipotential bonding is to limit the voltage at and around the pool from an INTERNAL SOURCE, the pool parts and materials themselves.

Like with equipotential bonding, grounding doesn't dissipate anything. Until the source is removed or de-energized, the possibility of a difference in potential is created, thus resulting in surge currents on parts NOT INTENDED TO CARRY CURRENT.

The ground ring was developed to allow for several lightning down conductors to be attached to the earth and provide a means for establishing a counterpoise at a building or structure. The perimeter bonding ring was established to allow for the 4-point connection from the conductive pool shell and to provide equipoential bonding of the perimeter surfaces fully around the pool, 3 feet out.




You have to go back to your theory days to remember that voltage is only the pressure or potential that is present between two or more objects. The only way to ensure no potential is present between two objects is to electrically bond them together. This way, no current can flow between those two objects using a humnan, or in this case, cattle as the circuit.

I guess this is good time to point out that we are indeed talking about THEORY and not LAW or FACT. We could all be wrong...

I forgot to mention one other significant difference between system grounding and equipotential bonding.

Equipotential bonding is a LIFE safety matter. There is no risk of fire, equipment damage, or structural damage from a lack of equipotentail bonding at and around a pool. It's only purpose is to protect PEOPLE from shock.

Grounding is a PROPERTY safety matter. Grounding does NOT protect people from shock or electrocution.


Also keep in mind that neither of these systems are absolute. One limits the voltage imposed (grounding), and the other reduces the potential hazard (equipotntial bonding). Neither allows for the operation of overcurrent devices, and neither protect the contents and equipment of the premise wiring system. Remmber, neither of these two systems are a component of the effective fault path.

It is interesting to note that there are likely millions of pools and structures in the US that do not have proper grounding or equipotential bonding. The current that can be present at a pool is so small that many people can feel the sensation. It is frequently called "tingle voltage" and is in the mA range. In other cases in can be fatal, if it causes you to slip and fall, or perhaps gasp for air while under water.

A lack of grounding of the system doesn't mean much either if that external surge event never occurs. Normally operating currents and fault currents do not rely on the grounding system to operate. So, if you are lucky enough to never have a lightning event, line surege, high-voltage cross-over, or some other surging event be imposed on your system, grounding does and means nothing.

Yep called topic drift.

But I think it is straight forward.
680.10 states to refer to the 680.10 table if wiring necessary for pool equipment is within the 5' distance.
So for a light niche I would say you need to maintain the 18" depth for pcv until you exceed the 5' distance.
Looks to me you can't infringe on the 5' distance for anything else but pool equipment.


Now have fun with things such as malibu lights and speaker wiring.(Would you call that pool equipment?)
If not it needs to be beyond the 5' distance.

Or another thought would be the required gfi outlet on a existing dwelling that the contractor trys to place it in a planter.In lieu of adding it on say a porch. But the feed runs less than 5' from the pool shell to get there.(is that pool equipment?)
Topic drift again.
But like you said we can't help it.

Is this fun yet?
The FBC was supposed to make a uniform code for us all. But we still have the subjective determination problem in the field.

680.10 allows wiring within 5ft of the pool under two conditions.
1. Wiring for pool associated equipment.
(See cover table 300.5 not cover table 680.10).

2. Wiring not associated with the pool where the property lines do not permit the 5ft separation.
(Table 680.10 Minimum Cover Depths).

I agree Mike but now, how do we determine what actually is pool equipment.
I don't see a definition!
Is a pool lite considered pool equipment? In my mind it does not.
It is a light fixture not equipment.

Also is the required gfi outlet pool equipment?
Looks to me like a outlet not equipment.

This was my feeble attempt to make a point of the dilemma in my prior post.
I guess I might have missed the point on a few statements but still where is some guide line on what pool equipment is. We can probably all agree a pool pump is equipment. But then what else is?

I would say that it's anything associated with the pool per article 680.

Pool lighting, pumps, heaters, pool cover motors, receptacles, etc. 680.10 comes into play when a shed (for example) in the back yard needs electric and the property line will not permit routing the wiring method beyond the 5ft.

From Mark Ode regarding depths of pvc.

Definition of equipment includes luminaires. ART 100

Paul to what does your comment apply to? Wiring methods as part of pool equipment, or other?

Pool light PVC.

Ruben,
When you refer to the "Red Barron" you really date yourself. LOL

That was the question.

Never heard the red barron term.
But I had my turn with him.
LOL.

Took a while to remember but another nemesis was Melvin Hunt in City of Dunedin.
Always nailed me for clearance on the pool panel.
Which I had no control over on a prewired home. Then of course the pool company stuck the pump right in front of the stub out.

Okay back on topic.
The world according to Mike and John.
The Pool lite is pool equipment.

So that means the depth is determined by table 300.5.
Correct?

So looking at table 300.5. A standard pool with a 4" concrete deck the pvc would need to be 4" below the slab. Column 3.
Correct? Regardless if it is a 120v or transformer 12v circuit.

In past I am guilty of this. I just lifted the mesh and laid the pvc on the dirt dropped the mesh on top of it. And they always passed inspection.

Let the fun begin. Again?

Ruben you are 100% correct!

And for less than a 4" thick deck?????????????

OMG, here we go again.
I guess it would fall under the 2" thick row which is 12" deep.
But now let's get really picky.
Most slabs are not a full 4"
If they use a 2x4 to form the deck it is only 3-5/8"
Since the code states under a minimum of a 4" thick concrete slab.
So how do you know you have a 4" thick slab?

Why - you look at the approved plans, of course!

Alas, 'tis true...most pool decks are not 4" cover . So the PVC for the pool light needs to be at the proper burial depth. This is one of the most flagrant violations that electrical inspectors (I like to think unknowingly) allow, here in our state.

Not to mention the fact that most PVC runs for pool lighting do not even begin in a deck area, but rather some part of the yard, and then continue on into the deck.

So have fun, and catch these burial depth violations!

You are a sick puppy looking for punishment from the masses.

But to have some fun under the deck it appears that you could dig a small trench and slide a chair under the pipe to allow 2" encasement and be out of the the issue.
Then of course deal with where the pipe extends from under the deck.