swimming pools earthing

You can put them in the earth if you like.

Or, the earth in them.

What do you want 16 edition 3rd amendment regs? or

the new 17th edition regs? which isn't out yet till Jan 2008 (thats if it approved) even if it is it wont be in practice till June 2008

OOOO so many choice's

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Thank you and good night

chapter 1
The IEE Regulations

chapter 2
Installation
Requirements
and Characteristics

chapter 3
Installation Control
and Protection

chapter 4
Cables, Conduits
and Trunking

chapter 5
Earthing

chapter 6
Circuits

chapter 7
Special Installations

chapter 8
Testing
and
Inspection

chapter 9
Data cabling
and Networks

Contents

Special Instalations --1. - Introduction --2. - Bath tubs and shower basins --3. - Swimming pools --4. - Sauna rooms --5. - Installations on construction sites --6. - Agricultural & horticultural --7. - Restrictive conductive locations --8. - Earthing for function & protection --9. - Caravan, motor homes, caravan parks 10. - Highway power & street furniture 11. - Heating appliances & installations 12. - Discharge lighting 13. - Underground & overhead wiring 14. - Outdoor installations & garden buildings 15. - Installations of machines & transformers 16. - Reduced voltage systems 17. - Marinas 18. - Medical locations 19. - Exhibitions, shows and stands 7.3.1 - Introduction 7.3.2 - Special requirements for swimming pools

Most municipalities in NY State require Ground fault interrupter protection in the power supply circuit. GFI s are available from most electrical supply houses and from Home Depot or Target. Relatively inexspensive to purchase and simple to install.

You need to state where the pool is in the ground (i.e. what country you are in). Regulations differ from country to country.

Unfortunately in the US it varies from state to state. Follow the IEEE standards and you should cover everything, probably better than what code says. Code may have some twists thrown in left over from the 19th century though...

Just do it right. When we moved into our present house I found out that the pool pump wasn't grounded at all! Scary stuff.

Case History:

I agree to check local laws, but, I can give you a general idea as I just re-worked one where swimmers were getting a shock when touching cleats (even while out of water attaching lane markers wearing tennis shoes), handrails, etc. (and not during electrical storms).

This was a 25 yard long 4 lane lap and aerobics pool owned by a SCUBA diving shop and Aquatic center in the USA. I used the National Electrical Code guidelines, local codes, but also common sense regardless of codes (overdoing it when in doubt). First, we double checked all pool pumps (they were all PVC water connections, but this doesn't matter). One motor was grounded by the frame and this was causing the ground fault breaker to trip. They just installed a new motor and someone grounded the frame with the ground wire. They were running off one pump in the meantime because the other kept tripping instantly. The service entrance split off the 220 VAC with a grounded neutral, to get 110, so, grounding the frame of the motor also gave a current imbalance which tripped the ground fault. After un-grounding the frame, it worked fine (this was not causing the shocks as it was tripped, but was just one more interesting fact where the electrician connected it wrong by grounding the motor frame; backwards from how you might think).

Where do the shocks come from? We learned that the utility had done some work in the area, but they wouldn't tell us what. Also, I saw a neighbor put a electric water heater out by the curb meaning he had fried one and connected a new one recently and he reported his feeder breaker was tripping (maybe he did something wrong?). All these things are clues for stray voltage.

Generally there are all types of stray voltages in the earth, so our goal was not to trace them down, but limit their influence to swimmers. The impedance of a human body can be much lower than other current pathways when swimming in a big wet bowl subjected to these stray voltages. Touching a metal frame will give a low resistance path for current. It only takes a few milliamps to stop a heart.

And who uses these aquatic pools? Seniors for water aerobics !! That means their heart is at water level when standing during aerobics and arms form a conduit across their heart when they touch things. So we red tagged the pool immediately and began the work!

Ground resistance was more than 20 ohms at the single ground rod (a bit high). We drove in various ground rods in strategic locations and exothermically welded the #6 bare copper ground wire to each rod to avoid corrosion of clamps (the rods must be more than 6-8 feet apart so they don't negate each other).

We broke into the building perimeter foundation and welded some ground wires to our ground ring to the rebar in the foundation to make a Ufer Ground out of the concrete. (Google Ufer Ground).

It was a liner pool, so we ripped out the liner. We cleaned all the metal joints around the liner top edge (aluminum rail with jumper clips) and heliarc welded all the aluminum joints to bond them into a solid ring, then bonded a ground wire in 8 places to this metal ring via welded tabs on the back side of the rail (chipped out the concrete). We welded a tab onto all cleats, hand rails, and where there was a slip joint (hand rails dropped into embedded pockets) we welded tabs across those joints and bonded them. So all metallic objects withing 6-8 foot of the pool edge were now positively bonded to our main ground ring made from # 6.

Now we needed to build a equipotential grid. We rented a concrete saw and got a blade with thickness equal to a #6 wire. We sliced up the pool bottom and sides into 12-18" squares, and also ran 3 rings around the foundation where you walk around the pool. We hammered in bare #6 in all these slices and exothermically welded them together where they crossed to make a giant "screen" grid, with drops off to each of our welded tabs for cleats and hand rails and the aluminum top ring. We broke out several places in the foundation where you walk and tied into the concrete screen in 8-10 places around for extra measure, again, always exothermically welding each joint (no clamps). The pool itself had no 'screen' in the concrete. That is why we had to build a grid. I didn't trust tying into 1-2 rebars only as they typically are NOT electrically bonded to each other in the concrete. You are allowed to use the rebar for a grid, but the squares must be this 12" x 12" square size and the re-bar welded to each other for a bond. We tied into the re-bar for fun, but, depended on our fabricated grid for the equipotential grid per code.

We grouted over all the cuts that were full of our bond wire. So we were bonded about as good as one can get everywhere. Each ground rod outside now measured less that 5 ohms ! Perfect. You must use a special clamp-on ground resistance tester (several thousands dollars). 4 of us did this in a week, including draining (fire truck pumper, letting the fire department have a training session and emptying the pool also), liner out, new liner in, and refilling (fire truck again).

No shocks reported in 4 years now.

Thank u all, thanks PetroPower

Thanks a lot.