Surface mount light to old pool shell

[Kwikee]

I have just started the process of our pool renovation and among other things, want to add a surface mount light. It appears the old niche type lights are a thing of the past anyway, but is there anything I should know about what seems like a pretty easy task?

From what I have worked out, I can core/drill a 25-30mm hole vertically in the pool wall, about 500-600mm down, then core or drill horizontally from the face of the wall to meet the vertical hole and there is the conduit line for the wire (12v), I'll then feed the wire down and out the wall face by a metre or so and then urethane seal the wires into the drilled hole, and epoxy the last 10mm or so flush with the pool wall face. This gives me watertight wiring. I'll then attach the mounting plate to the wall, wire the light and coil the excess in the back, and fit it to the mounting plate. On top, I will chase out a channel for a 20mm PVC conduit to run to go back to the transformer and I should be done.
So what I need to know is, is there a standard or accepted depth the light should be fitted below the waterline? I figured about 400mm (16") seems about right but I don't know. Also, where is the best place to position one?

The pool is this shape (having just removed the pavers that were laid on top of this concrete):
[attachment=0:e8f733sg]IMG_0688.jpg[/attachment:e8f733sg]
I though on the back wall next to the ladder, otherwise on the right hand side straight part, about 1/2 way along.
Ideas? Anyone done this and have tips? Cheers and thanks for reading!

 

[dtlight]

In the US you wouldn't be allowed to do something like that because the wire has to run in conduit from the light to the deck box. The way you are proposing will make it very difficult to work on the light fixture after all the epoxy sets. In the US the minimum depth of a niche light fixture is set by the electrical code (so that the fixture is not in line with your heart if you are hanging on to the wall), and for niche less non conductive fixtures you are required to install them according to the manufacturers instructions.

 

[Kwikee]

@dtlight- I think you might have misinterpreted what I've said. For starters, the light is low voltage @12V so the risk of shock is minimal. The cable would indeed run in a conduit from the power source to the light, the epoxy seals the cable into the conduit with a metre or so protruding, which is attached to the light via a waterproof seal. The cable and method of sealing to the light are rated for water immersion. It is an LED light and the wiring and all electronics are encased in epoxy resin also. To work on the light, you unscrew it from the mount, and unwind the wire that is coiled inside the light so that the light can reach the pool deck.
I believe these type of lights are family common and the risk of injury very slight. Low voltage garden lighting systems etc are very common here and are not nearly as well designed to prevent electric shock.

 

[dtlight]

You should check with your AHJ (authority having jurisdiction)about what you are proposing. In the US the requirements for low voltage lights are more stringent than for line voltage because the GFCI's circuit protection doesn't extend to the low voltage side of the transformer. The risk of electrocution when your skin is wet is higher, particularly in non salt water pools.

 

[Kwikee]

Then how do you wire surface mount/niche-less lights? The last section of the complete wire will always be exposed to pool water. I believe most lights have at least part of the wiring exposed, otherwise you'd have to drop the water level to work on every type of light, which I don't believe you do.