Qn For The Electricians - Pool Lighting Safety With Bear Wires When Light Is Removed?

[samran]

I guess some of us have seen that movie 'Syriana' where the kids jump in the pool with a faulty electrical light and they are killed by electrecution.

With that in mind - this morning I went for a swim in our apartments pool and noticed that one of the round underwater lights has been removed. In its space is a cavity where the light should be, and (what I assume to be) the electrical wiring wrapped up neatly with what looks like tape wrapped around the end where it should connect in with the light.

Speak to the pool manager and ask him what the story was and he tells me the light has been removed for a while. I tell him that I am worried that there is a risk now that someone could get electrecuted to which he said "the chang (electrician) said that there are only a few volts which go through these lights".

My great (uneducated) worry is that isn't the correct answer - and that if some numpty came along and turned on the lights (they are currently off) then the pool is a litteral killer.

So - would be grateful if someone could give me a clearer view of what the real deal with this situation.

Cheers in advance - samran.

[Crossy]

One would hope that these are SELV (low-voltage) pool lights in which case the manager is correct.

However many older pools do have mains lighting. It is invariably this type of light that results in pool electrocutions!

Pool lighting is (theoretically) sealed against water ingress, the light fittings are removed and brought to the surface on a waterproof flex in order to replace the lamps.

If the taped wires are inside the capsule and there is no water in there then there is little danger and you can swim in reasonable safety. If the wires are actually in contact with pool water I would be going nowhere near the pool even if assured that it's SELV unless I knew the wires were completely isolated.

One wonders why the light has not been replaced, if money is the issue I would be wondering about the safety of other pool related equipment.

[samran]

Hi Crossy

Thanks for the response.

Yep - wires are in contact with the water. Not in the caspsule - just wrapped up in the cavity in the wall where the capsule/lighting should be.

ed - the complex is less than 2 years old - so presume they are the more modern version of the lights.

Edited January 14, 2013 by samran

[Phronesis]

At the other end of those wires will be a step down transformer taking the 220v down to 12v. Corrosion, a short, or a dead cockroach could easily see a bridge created between the 220v and 12 v windings. The result may well be fatal.

Swim at your own risk.

Edited January 14, 2013 by Phronesis

[ThaidDown]

If the 'electrician' is sure that there is only low voltage on the wires then ask him to be in the pool while you switch the lights on and see his reaction..

edit..spelling

Edited January 14, 2013 by ThaidDown

[samran]

If the 'electrician' is sure that there is only low voltage on the wires then ask him to be in the pool while you switch the lights on and see hgis reaction..

my thoughts as well...

Edited January 14, 2013 by samran

[Naam]

One would hope that these are SELV (low-voltage) pool lights in which case the manager is correct.

please correct me if i'm wrong Crossy but "in my book" it's not the volts but the amps which can kill.

[Tywais]

One would hope that these are SELV (low-voltage) pool lights in which case the manager is correct.

please correct me if i'm wrong Crossy but "in my book" it's not the volts but the amps which can kill.

That is true but current is directly related to voltage and skin resistance. Lower voltage, same skin resistance less current. Chart below with percentage of population skin resistance from hand to hand. Knowing your background Naam, I'm sure that I'm not teaching you anything new though.

[ksamuiguy]

Pool lights are now, almost always 12 V, the problem is the transformer, if it shorts internal it could put 220V in the pool.

We always install "pool lighting transformers and a Safety Breaker on the pools we service.

Most pool light failures are caused by the installer not sealing the sheath of the cable to the light, the water wicks doen the cable into the light fixture and fills the light with water. Light comes on and bulb blows or connection is corroded by the chemicals.

We use "3M rubber Fusing tape and heat shrink tubing on all of our underwater or underground connections, as well as Ground Fault breakers on the transformer primary. "Safety is No Accident"

[Crossy]

I would hope that all new pool installations are SELV, but there are enough pool electrocutions reported that they can't all be transformer failures.

[Naam]

One would hope that these are SELV (low-voltage) pool lights in which case the manager is correct.

please correct me if i'm wrong Crossy but "in my book" it's not the volts but the amps which can kill.

That is true but current is directly related to voltage and skin resistance. Lower voltage, same skin resistance less current. Chart below with percentage of population skin resistance from hand to hand. Knowing your background Naam, I'm sure that I'm not teaching you anything new though.

the part of my background concerning "sparks" was rarely used during my professional career. that's why most of the (many rainy seasons ago) acquired knowledge has faded or is missing completely

[Naam]

Pool lights are now, almost always 12 V, the problem is the transformer, if it shorts internal it could put 220V in the pool.

We always install "pool lighting transformers and a Safety Breaker on the pools we service.

Most pool light failures are caused by the installer not sealing the sheath of the cable to the light, the water wicks doen the cable into the light fixture and fills the light with water. Light comes on and bulb blows or connection is corroded by the chemicals.

We use "3M rubber Fusing tape and heat shrink tubing on all of our underwater or underground connections, as well as Ground Fault breakers on the transformer primary. "Safety is No Accident"

aren't all pool lights "sealed beam"?

[samran]

Just to let everyone know - a chat to the management has seen the light replaced in 24 hours.

One of the benefits of staying in a nice place I guess

[Phronesis]

Pool lights are now, almost always 12 V, the problem is the transformer, if it shorts internal it could put 220V in the pool.

We always install "pool lighting transformers and a Safety Breaker on the pools we service.

Most pool light failures are caused by the installer not sealing the sheath of the cable to the light, the water wicks doen the cable into the light fixture and fills the light with water. Light comes on and bulb blows or connection is corroded by the chemicals.

We use "3M rubber Fusing tape and heat shrink tubing on all of our underwater or underground connections, as well as Ground Fault breakers on the transformer primary. "Safety is No Accident"

aren't all pool lights "sealed beam"?

In the real world...

[Crossy]

Just to let everyone know - a chat to the management has seen the light replaced in 24 hours.

One of the benefits of staying in a nice place I guess

Whilst it's good news that the issue has been fixed, it should never have been left like that in the first place SELV lighting or not!

If you had not complained would it have required a death to prompt repair?

[samran]

Just to let everyone know - a chat to the management has seen the light replaced in 24 hours.

One of the benefits of staying in a nice place I guess

Whilst it's good news that the issue has been fixed, it should never have been left like that in the first place SELV lighting or not!

If you had not complained would it have required a death to prompt repair?

Very true - things like this being overlooked certainly worry me - which is why if I ever buy my own place here Crossy, you'll be my electrician....

Edited January 18, 2013 by samran

[electau]

Pool lighting should be less than 50VAC (SELV) RCD protection on all socket outlets, and equipotential bonding within a defined pool area.

[Crossy]

Pool lighting should be less than 50VAC (SELV) RCD protection on all socket outlets, and equipotential bonding within a defined pool area.

My highlight!

The number of pool electrocutions reported in Thailand suggest that much is not!

[electau]

Equipotential bonding and earthing is of unmost importance to minimise voltages between different parts of the pool.