I recently taught a seminar at the Atlantic City Pool & Spa Show and found that there may be some confusion regarding certain aspects of electricity, especially pertaining to lifts and the meaning of grounding and bonding.
Bonding and grounding
I had a little time today, so I went on the Internet to see what it said about pool bonding, and I noticed a lot of people making the comment, “My pool doesn’t have bonding. There’s a wire there hanging, and it’s not doing anything, it doesn’t go anywhere, and I don’t know if my pool is bonded.” All these people on the Internet are talking about this bonding that they don’t have.
A comment I received after my class at the pool show stated, “It was nice that you talked about the bonding, but people need to understand why it’s necessary — besides the fact that it’s in the code.”
The name actually is equipotential bonding and it basically means “equal potential bonding.” The concept is that you want to get the pool water and everything that you could touch while in and around the pool to be at the same potential, or voltage. Potential is voltage, and you want all equal voltage. You don’t want any difference in voltage between one side or the other, whether you’re in the water or on the concrete.
For example, if you’re going from the ground to the pool, and you’re touching a metal railing, you want everything to be at the same potential. If a difference exists and it’s lower than 4 volts, you’re going to get a little tingling. If that difference is higher than 4 volts, you’ll have more than a tingle.
Bonding all the equipment together ensures the same potential, or voltage, anywhere in the water or around the pool.
I’ve also seen confusion about bonding versus grounding. I try to distinguish it when I teach my classes, but everyone, myself included sometimes, uses the words interchangeably. They shouldn’t.
Part of the answer is understanding the idea of an equipment grounding conductor. It’s a hard topic even for electricians. First, visualize the bonding scheme: You have all these wires tied together around the pool. You have the rebar itself. You’ve got the lift, railings and diving boards bonded together. All the fixed metal components around the pool, plus the water, are bonded together. Then you go with a No. 8 wire to the pump. That’s where the bonding wire ends.
Now, going from the motor, generally back to the home, is a wire that could be as small as a No. 12. That wire is the equipment grounding conductor — not a bonding conductor. The equipment grounding conductor comes from the house panel and goes to the pump motor. Then on the pump, there’s a lug that goes to that No. 8 wire that goes to the bonding of all the equipment.
The electrician is trying to make the bonding at the pool the same potential as the grounding conductor coming from the house. So you’re grounding through your house panel and attaching to the bonding wire, which will make it the same potential. That ties in with the definition of equipotential bonding.
If there’s a short of any kind, the equipment grounding conductor allows the short to go back to the source of power and trip the breaker. The equipment grounding conductor grounds the pool equipment, in this case the pool pump. That’s the difference between bonding and grounding.
Lifts and bonding
The National Electrical Code requires any fixed equipment made of metal that’s within 5 feet of the pool to be bonded. This includes lifts, whether fixed or portable, hard-wired or battery-operated. Some professionals may be unaware of this and install lifts without bonding them. This goes against code and could potentially cause a safety problem.
Many professionals believe that for certain lifts, all they need to do is cut a hole in the deck and bolt the lift in place, but more work may be required. Typically, lifts are bonded by attaching the anchor or base to the existing bonding wires around the pool, to the rebar around the pool. This may require more cutting into the deck than expected to reach rebar. While that’s not the only way, it’s usually the best method.
Lifts also can be treated similarly to handrails. Professionals can put a metal cup or sleeve in the concrete and attach that to the bonding wires where the rebar is attached to the bonding. It’s completely fine to install a portable lift that is placed into a hole or sleeve of some type, as long as that hole or sleeve is bonded. I’ve also seen some with a flat metal base bolted to the concrete deck, which is fine as well, provided that something is attaching that metal frame to the bonding grid.
Lifts and third-party listing
Until recently, I worked as a construction official in New Jersey, which is known as a fairly strict state. There are hundreds of towns, and since inspectors have the authority to decide whether something meets code, there typically are different interpretations.
For example, there is confusion out in the field about whether or not a lift has to be listed by a third party laboratory. Most are battery-operated, and all the components related to the battery system are generally tested and listed by a third-party testing laboratory. But the whole lift itself is not listed. It’s similar to barbershop poles: All the components in it are listed, but the whole package, including the housing, is not. That’s where it gets a little touchy: Some inspectors will say it isn’t compliant and won’t pass it.
But there is no lift that I know of that is listed in its total package.
Unfortunately, professionals may have to convince the building official that there are no lifts that are listed. In article 680 of the NEC, it doesn’t say that everything used for a pool has to be listed. You are not violating the code per se. That’s where I would be able to approve a lift of that nature.
