swimming pool electrical question

zagshdjfkgl wrote:

edge. It the place is wired with three phases, which most are, you

circumstances arise. GFCI may not work fast enough, and do not rely on just them to provide protection. Just use your battery only, charge at night.

In thirty five years of electrical work I have only run into persons this confidently uninformed among second year apprentices. What matters is the voltage to ground not whether the supply is single or three phase. The reason that the US National Electric Code prohibits the installation of receptacle outlets within ten feet of the waters edge is that the length of cord available on ordinary portable devices for consumer use is seldom longer than eight feet. That prevents the portable AC powered device from falling into the pool while it is still connected to the outlet. Unless the power supply brick together with both it's AC and DC cords is longer than ten feet there is no hazard. A portable GFCI might make good window dressing but for bomb proof safety you may want to consider obtaining an isolation transformer. These are used in the heavy steel construction and repair environments to protect workers who must use power tools while in intimate contact with conductive surfaces. The secondary side of an isolation transformer is not connected to ground in any way. That means that making contact with the power that it produces is far less hazardous because grounded surfaces will not complete the circuit. In order for isolated power to electrocute you you have to make contact with both sides of the isolated circuit on opposite sides of your body. It seems to me that that approach would take so much explaining as to cause more trouble than it prevents.

-- Tom H

------------------------------------------------- Ted Rubberford. 'The Man In The Red Latex Skintight Suit'

In a swimming pool you do have an 8ga copper bonding pool steel (and any other metal bigger than the palm of your hand) to the pumps and lights, along with the EGCs back to the srervice grounding bus so ground is ground.

They go out of their way to make it so.

No, you are confusing the neutral current in a three-phase wye system with ground. They are *not* the same. An imbalance of the three-phase loads in a building will cause currents to flow in the neutral. But the deck, pool-frame, and other exposed metal within the pool area is *bonded* together and connected to *ground*. The neutral and ground are only connected at one place, the service entrance.

A significant neutral current (caused, perhaps by a large unbalance in single-phase loads) will *not* create a voltage differential between the pool, pump, filter, decking or any other properly *bonded* equipment.

The GFCI protects a user of electrical appliances by interrupting the power whenever a mismatch is detected in the current through the out-going phase and the returning neutral. Or if the neutral inadvertantly connected to ground someplace beyond the GFCI (again, remember that ground and neutral are only connected at one place, the service entrance).

daestrom

Hey little Boy!

You have an attitude problem as well as a severe lack of electrical fundamentals. Please do some seroius research before you use nasty words on someone far superior to you.

Do you always resort to personal insults when you have no knowledge of the topic?

What does it explode in?

Mike F

I am not even sure where to begin with all the bad information you managed to put out in a single post.

I think you are confusing ground and neutral, but in any case all three phases use the same neutral.

Very few houses are wired with anything other than 240/120 single phase. There is such a thing as 2 phase but it is almost never seen. If one were stupid enough to introduce a dead short across 240V like you are suggesting by plugging cords from one socket to another, it is unlikely anything would happen other than the tripping of a breaker. No vaporizing wire. probably not even a spark.

Why do you have to have a laptop at a pool anyway? No one likes swimming in a laptop contaminated pool. Or getting Zapped by an electric wire

what is wrong with pen and paper? They might get stabbed by the pen, and the paper could cover their mouths, while breathing in the pool.

Most all buildings are wired with 3 phase,

Not hardly.

Bob AZ

Don

Thanks for your help folks. I think I'll try the portable GFCI. It sounds like a good compromise that the pool manager can live with.

Try to get the applicable NEC quote from the pool manager. I would guess he will not do this. Till then the portable GFCI thing is a good idea.

Bob AZ

been around long enough to remember retrofitting chillers with torroidals and cts and interlocking low voltage mag locks between two high impedance dc relays. back then it was almost only used on high voltage none in residential none in commercial late 60`s when i started this trip. you still dont have a clue