grounding a SWG

[doriec]

When we had our pool installed 3 years ago, the installer forgot to put in the ladder until after the pool was finished. The sidewalks were all poured when he decided to install the ladder. As a result, the ladder is not hooked to the pool's electrical ground system. Now we are thinking about installing an SWG and we are worried that the salt will have an adverse effect on the ladder. There is NO way to dig up the sidewalk to run a wire from the ladder to the pump to ground it. Bleach went up .30 a gallon this year where we live, and we use lots. That is why we would like to convert. What would happen if we got the SWG without any changes to the ladder? Thanks. Dorie

[Poolsean]

Dorie,

As long as your pool equipment and Salt Chlorine Generator are bonded, you shouldn't see any problems with damage to your handrail. Again, make sure there is a bonding wire on the pump motor (this is usually a solid copper wire, or green ground wire) to a grounding rod into the dirt. Connect a bonding wire from the grounding rod (or motor) to the bonding lug of the salt system.
This should help keep stray voltage from the pool.

The design of a salt system is such that there shouldn't be any stray voltage radiating from the cell and into the pool. UL1081 guidelines limits this from happening. However, any electrical device can radiate stray voltage if not installed properly. Unfortunately, the bonding wire attachment is one easily overlooked by the installer.

Hope this helps.

Sean

[gwrace1]

According to the NEC electrical code the bonding wire loop is not a grounding wire. It simply keeps all electrical and metal components at the same electrical potential to avoid a "difference of potential" that could cause a shock.

The only connection to ground would be threw the circuitry where the bonding screw attaches to the pump motor.

The ground rod and connection to the sub-panel is a separate connection required for a sub-panel wired from a main feeder panel.

Just remember that proper bonding and grounding are two separate requirements for pools.

[doriec]

Thanks for your information. I have more questions though. We talked to the electrician, and he said that our panel, pool equipment and pump is grounded with a rod to the ground. He suggested that we hook a ground rod and wire to the ladder and run it into the ground. He says this will take care of the ladder since it was installed after the pool was built. Do you agree? Thanks, Dorie

[JohnT]

Thanks for your information. I have more questions though. We talked to the electrician, and he said that our panel, pool equipment and pump is grounded with a rod to the ground. He suggested that we hook a ground rod and wire to the ladder and run it into the ground. He says this will take care of the ladder since it was installed after the pool was built. Do you agree? Thanks, Dorie

Your electrician is misinformed. He's not alone though, as most electricians don't understand code when it comes to pools. The wire from the ladder needs to go to the bonding circuit for the pool. This is a wire that connects to all of the metal objects that are close to the pool or that contact the water. Things like the pump motor, ladders, hand rails, slide bases, light housings, diving board stands, SWGs, heaters, fences, deck rebar, steel pool walls, metal coping, and I'm sure there are others I've neglected to mention. These things are all to be wired together, but there is no requirement for grounding. Have your electrician refer to the 2005 NEC, Article 680 where it says:

"equipotential stray voltage bonding conductors aren't required to extend to any panelboard, service equipment, or an electrode."

What this means is no ground rod is required. The reason for the bonding wire is to keep everything that could come in cantact with a swimmer at the same voltage. Grounding this bonding wire usually occurs by way of the bonding lug on the pump motor, but is just coincidental. Additional grounding electrodes serve no benefit, and may make your pool subject to stray voltage problems.

Grounding your ladder seperately from the rest of the bonding system isn't the thing to do. You need a wire to the bonding system. Sometimes the wire can be epoxied into a nearby control joint in a concrete deck without looking too bad.

[doriec]

John, What is the worst that can happen if the pool ladder is not bonded? Thanks, Dorie

[JohnT]

John, What is the worst that can happen if the pool ladder is not bonded? Thanks, Dorie

Assuming everything else is bonded properly, the big concern would be if something like an extension cord was drug up against it and had bad insulation. The ladder alone, IMO isn't a very big risk IF everything else is good.

[Mike_in_NJ]

Worst that can happen? Someone can die. I'm being serious here, that is the worst that can happen.

Also what can happen when the different metal parts are not bonded together is an increased risk of metal corrosion.

"there is no way to dig up the sidewalk ..." There is -always- a way to do something, some ways are better than others. There ought to be the original bonding wire underneath the sidewalk connecting all the metal parts of the pool together. All you have to do is connect a new bonding wire from the ladder/sockets into the existing bonding wire(s). Use a diamond masonry blade and cut out the section of sidewalk with the ladder, remove the concrete, connect the bonding wires the way they should have been done in the FIRST place, repour the small section of concrete. Done. Other choices might be to use the diamond blade and run cut line(s) out to the edge of the sidewalk from the ladder and sink the bonding wire down in the groove. Connect the ladder to one end of the wire and then dig up dirt to connect the other end of the bonding wire into the existing bonding wire. Make the groove(s) look like control joints and it shouldn't be too noticable.

The install was never done right or completed if the ladder wasn't bonded into the bonding circuit. I strongly suggest you fix it. You might play hardball with the installer and insist he fix the problem.

Rgarding the risk, you know it isn't right. Fix it. IMHO.

[PoolDoc]

Hi Dorie;

As is often the case, sudden changes prompt sudden action. In your case, you are looking at an increase in bleach prices, and have decided to go with an SWG.

Now, I think SWG's are often helpful, and -- unless you get a bad one, or a bad installation -- almost always more convenient than bleach. But, they aren't cheaper, even with bleach at $1.30 per gallon. Several threads, in the SWG are centering on annual operating costs in the $60 - $100 per season range. The (corrected) calculations I've seen seem reasonable. But, even at $1.30 per gallon, not many pools will spend more than $100 per season on bleach. If you did, you probably need to post your chemistry info, so someone can make sure you aren't doing something wrong.

Keep in mind, too, that most SWG users here *still* use bleach for start up, heavy bather loads, and so forth.

When you add in the $500 - $1500 installed cost of an SWG, you aren't looking at any savings, even if you divide the cost of the SWG over 20 years.

This doesn't mean you shouldn't get an SWG; it just means you shouldn't think that doing so will save you money.

On to the codes . . .

I can verify, from much experience, that most electricians don't know how to apply the pool section of the NEC, and even fewer understand WHY those requirements exist or WHAT they accomplish. JohnT's explanation of the difference between bonding and grounding is correct; Mike_in_NJ correctly notes that lack of bonding can lead to more corrosion, but it's also true that bonding itself can increase corrosion, under certain conditions.

And, Mike_in_NJ is also correct that bonding requirements have safety concerns at their core. But, will the lack of a bonded ladder substantially increase your risk of injury by electric shock? The answer is, "Only very rarely, and usually only if something else is wrong."

To put it another way:

• I won't let my family swim in an unsanitized pool, and those are very common.
• Until they could swim 400 yards non-stop, I wouldn't let my boys swim, unless an able swimmer (preferably a lifeguard) was scanning the swim area continuously. Sometimes, that meant that my wife or I had to 'be' the lifeguard, at pools where the guards goofed off.
• But, my family does now swim at pools where not all the deck hardware is properly bonded.

Bonding is an excellent idea. But, my judgement is that, in the absence of other serious problems (and it's true, I do have the luxury of usually knowing a lot about the design and construction of the pools where we swim), lack of a bonded ladder doesn't really concern me. It's a risk, of course. But, it's almost certainly not as big a risk as the risk of dying from aflatoxin poisoning my boys face each time they eat peanut butter.

So, what am I saying?

1. Don't get an SWG because it's going to save you money. Get it, only if the other benefits of an SWG are worthwhile to you.
2. Don't bond because of a risk of increased corrosion: there's not much evidence to support that.
3. If you are hypervigilant about risks, then you probably should be pay what it costs to get the ladder bonded. But, if you ever allow youngsters to swim without having adult eyes on them every single minute they are in the pool . . . then you are worrying about minor risks, when you should worry about more major ones.

Hope this helps.

Ben
PoolDoc

[Waterworks]

Rather than worry about cutting up your deck or any issues about bonding or ground, just get a Saftron ladder. www.saftron.com
They really are nice looking and come in different colors to coordinate with your decking.

Brad
www.waterworkspools.com