EBG

Status
Not open for further replies.
jwelectric

jwelectric

Senior Member
Location
North Carolina
After doing a search I find all the threads are closed so I started another to rehash the EBG around bodies of water namely hydromassage tubs.

Bonding requirements first appeared in the 1999 edition 680-73 and was versed; All metal piping systems, metal parts of electrical equipment, and pump motors associated with the hydromassage tub shall be bonded together using a copper bonding jumper???..
This was moved to 680.74 in the 2002 cycle but the verbiage stayed the same.
In the 2005 edition the verbiage was changed by a proposal by the TCC to read; All metal piping systems and all grounded metal parts in contact with the circulating water shall be bonded together????
This brought forth a debate concerning the word ?and? and whether or not it was a compound sentence meaning all metal pipes plus anything in contact with the water.

During the 2008 cycle verbiage was added to state that this #8 was not required to extend to a panel or electrode but the debate of the intent of the first 15 words of that section continued in debate.
Here is the Staff Note included with NECPlus; The bonding required by 680.74 is intended to create a local equipotential plane, and the equipment grounding conductor of the branch circuit supplying the hydromassage tub provides a path for ground-fault current.

In the 2011 cycle the verbiage was once again changed to include: The 8 AWG or larger solid copper bonding jumper shall be required for equipotential bonding in the AREA of the hydromassage bathtub and shall not be required to be extended or attached to any remote panelboard, service equipment, or any electrode.

Now to the questions at hand, does the #8 that has been required at a hydromassage tub for the past five code cycles require any metal pipes in the ?AREA? of a tub to be bonded or does it mean that no EBG is required at all?
Is it only anything that is in contact with the water in the tub or does it include the water that is associated with the tub such as the mixing valve used to fill the tub?
Is this a compound sentence which says; All metal piping systems shall be bonded and all grounded metal parts in contact with the circulating water shall be bonded together?

Thank you for taking the time to read this lengthy post and responding.
 
Mike, there's no right answer, still.

Mike Holt had a lapse in judgment and invited me to sit in on his 2011 taping of "Understanding the NEC, Volume II" which covered this section. One of the most notable moments was to witness firsthand six other code junkies and Mr. Holt all try to untie this knot while taping, and Mike's final response was essentially, "CMP 17 really needs to get their stuff together - Article 680 is in shambles at this point." :)

You can read this section any way you want, and it's objective is questionable to boot. There is really no good reason to require anything special of a bathtub. The lukewarm equipotential bonding attempt does not achieve equipotential bonding even read to it's most strict interpretation, because I can have an army of grounded metal surrounding the victim that does not require bonding.

Rob (infinity) had a proposal pass for the 2014 NEC that makes it clear that they intend to bond together only metal parts and piping in contact with the circulating water, leaving the mixing valve unbonded at the tub.

It clarifies their intent with the requirement, but leaves their "theory objective" wide open to question. 680.74 accomplishes nothing as far as I can tell.
 
George,
If I understand correctly Panel 17 only accepted the word “BOTH” and the rest stands as is. In other words the Panel stands by their statement, “The bonding required by 680.74 is intended to create a local equipotential plane, and the equipment grounding conductor of the branch circuit supplying the hydromassage tub provides a path for ground-fault current.”

Panel Statement:
The panel clarifies that the word “Both” replaces the existing word “all” at the beginning of the first sentence. Otherwise, only the changes shown in legislative text are intended


It is very obvious by the continued reference for the past 5 code cycles that Panel 17 wants the #8 installed for some reason.
 
Last edited:
Mike, not that this means anything but I have never seen anyone bond the metal piping from the copper water lines to the tub motor. Most everything we do today has plastic so there is no metallic piping system involved and as such it would not make sense to bond the valves, faucet, etc.

BTW, there are specs on some tubs which require the bonding to go back to the panel. Yes, hydromassage tubs-- I have never seen that done either.
 
Dennis Alwon said:
Mike,
Click to expand...

I know of where the stubs to the tub were copper and the rest was a non-metallic pipe that was required by the Code Official to be bonded and they used this slide for their support. Yes I know that the slide is not enforceable but couple that with comments made by Panel 17 and it carries a lot of weight.

680742.jpg


If the instructions including with the listing and labeling requires the #8 to go to the panel then by 110.3(B) it would be required by the NEC. I don?t think this is part of the listing and labeling but instead a recommendation of the manufacture of the tub.
 
jwelectric said:
If the instructions including with the listing and labeling requires the #8 to go to the panel then by 110.3(B) it would be required by the NEC. I don?t think this is part of the listing and labeling but instead a recommendation of the manufacture of the tub.
Click to expand...

I have been told by UL that the instructions are part of the listing. Frankly they didn't care what the instructions stated as long as the tub passed the test that they were asked to provide. They don't care what the NEC states as that is not their issue.

I think gus had the actual instructions that required this bond. Maybe he will chime in
 
jwelectric said:
I know of where the stubs to the tub were copper and the rest was a non-metallic pipe that was required by the Code Official to be bonded and they used this slide for their support. Yes I know that the slide is not enforceable but couple that with comments made by Panel 17 and it carries a lot of weight.
Click to expand...


I'm more than half convinced at this point that many on the CMPs have no business being there - ready to join my hostile takeover? :D
 
You may be right about the instructions as I found the one Gus posted. The approved bond gives us a way out- I guess

With a #8 solid copper wire, bond the heater to the house electrical panel or approved local bond. A bonding lug is
provided on the heater. With another #8 solid copper wire, bond the pump/motor to the house electrical panel or
approved local bond. A bonding lug is provided on the pump/motor.
Click to expand...
 
Status
Not open for further replies.
Top