Underwater Lighting

egorleski

Member
Hello all. I was wondering what if any experiance anyone here has had with either underwater fixtures or focusing lights through water. Im interested in trying lights like comercial pool lights and maybe those rope lights that are fully encased in plastic although that idea is slightly scary. I wonder has anyone ever tried building a plexiglass box thats waterproofed and has some fort of amibilcal cord to relase heat and for the power cord to go out of? cause then you could use standard lights...

just seems like an interesting topic to discuss.....
 
egorleski said:
Hello all. I was wondering what if any experiance anyone here has had with either underwater fixtures or focusing lights through water. Im interested in trying lights like comercial pool lights and maybe those rope lights that are fully encased in plastic although that idea is slightly scary. I wonder has anyone ever tried building a plexiglass box thats waterproofed and has some fort of amibilcal cord to relase heat and for the power cord to go out of? cause then you could use standard lights...

just seems like an interesting topic to discuss.....

I did metomorphosis a few years back and lit through water from underneath where we had plexi cut outs. Now if your trying to light in swimming pools thats a completly different story. You can buy "underwater" fixtures that are pretty bright and color the water well. As far as throwing a s4 in a plexi box and throwing it in the water goes not such a good idea. Also remember to use GFI's on everything near water. Are you actually wanting to do this or just start a flame war?
 
i mostly want to hear people ideas of how to do it. and ways they did it in the past. we used a similar method as to what u mentioned when we did metamorphoses.
 
Yeah, I'm not so sure I'd try to put a conventional light in any kind of underwater application. Too much heat generation, it'd probably melt whatever apparatus you rig up, not to mention how hard it is to truly waterproof any enclosure.

I've worked on fountains and pools with submerged lighting. I know Hubbell used to make a good underwater fixture (bronze, thick glass, used a 90PAR38 lamp, bright as all get-out) that had potted leads and bases and a thick rubber gasket to keep it dry inside. I'd spring for something like that rather than trying to rig up a waterproof enclosure big enough for a stage instrument.

Ya know, if you have to shoot "through" water... is there any way to shoot "under" the water? i.e. space under the pool you're trying to light where you could put a plexiglass panel fully waterproofed and sealed and sneak an instrument in under that, like firing through a window in the water? There's got to be a way to do something like that. Just remember the heat load you have to deal with and the materials around and how they'll react to heat and water, not to mention electricity.

In the water, a potted and sealed fixture is the way to go.
 
leistico said:
Yeah, I'm not so sure I'd try to put a conventional light in any kind of underwater application. Too much heat generation, it'd probably melt whatever apparatus you rig up, not to mention how hard it is to truly waterproof any enclosure.

Actually, no. The water will cool the fixture if fully submerged. Some of my dive lights are very clearly marked not to be used except when submerged because of the high heat output. The little one that I bend that rule on I know I'm playing with killing the lamp and having it on for more than 30 - 60 seconds at a time the lens and housing around the lamp really heats up.
 
ya, those dive lights are made for that, kinda like the potted fixtures lesitico was talking about, however I would think that if you took a conventional light and mounted it to a plexiglass box underwater, the plexiglass may not have enough heat transfer capability to dissipate all the generated heat, and would probably fail at being waterproof once heated. The layer of air between the water and the lamp would act as a layer of insulation. Air is a GREAT insulator (which is why winter coats are big and poofy and why windows have a layer of air (or other inert gas) inbetween the panes of glass) Then again, I could be wrong, it's happend plenty before!
 
I would like to second Peter on that one, If you have a 2' box and slap a 575 or 750w s4 in it and turn it on at full that box is going to get up to a few hundred degrees rather quickly. I do not believe that a plexi box could transfer heat fast enough to not overhead and cause a leak.
'
 
The approach I would take was leistico 's idea of buidling the floor of the pool a foot or two over the actual ground so you have a crawl space you could put fixtures in.
 
We own a pool supply store, and honestly, dont go with pool lights. They aint cheap and have no focus quality at all. Plus, they need to be hard wired or wont work and are a pain to use. A simple fixture shining into a plexiglass tank wall will give the same thing, just dont shine onto the water.
 
Hey sorry for the bump guys, but I figured it'd be better than starting a new topic all over again.

I'm working on a show right now which has a fountain on stage. As would pertain to the thread, the lighting designer wants the pool/fountain to be lit. I know that everyone's been pretty much saying to just stick with conventionals run through GFIs (question: can you run a fixture -> gfi -> dimmer? I would think so, but), but its a theater in the round and nonsubmerged fixtures might look a bit wonky on stage (and I'd be hesitant to put them underneath and enclose them, because of heat/gravity issues. Though LED fixtures would take care of the heat...)

So does anyone else have experience with underwater lights? I did some searching online and found mostly really expensive lamps designed for preexisting pools. Am I missing something, or is that really all that's out there?
 
With the Popularity of Home owner DIY fountains nowdays the market is flooded < pun intended> a a large variety of wet application, submersible lighting options. Check the pond section at your local Home Depot, or Lowes. I bet you'll find a ton of things that are usable.
 
I have also found some great underwater MR-11 fixtures that I have used in shows. I don't remember where a got them, but it was definitely a place that sold fountain/fish pond equipment. They had a built in fuse and transformer and came in sets of three. Worked great.
 
Wow, thanks so much for the input. Somehow the words "underwater lighting," "pool lighting," "submersible lighting," "waterproof lighting," etc. get me nothing, and suddenly I find a wealth of underwater LED, MR-11, and more. You guys rock. :cool:
 
I belive that Intermatic-Malibu company, the same one that makes the classic low voltage outdoor lights, also makes an MR 16 or 11 submersible low voltage light. These should be available at Home Depot.
 
I think that the folks over at Weidamark (suppliers of the famous Wiedamark LED par64) have some underwater LED lights. Give their site a visit, see if it's what you need.
 
I passed on some links and info to the LD, who's thinking about LED fixtures.

Quick question I just thought of though; for those of you who have done this before (or those who haven't), would you recommend slightly cloudy-ing the water so that it carries the color better, or is there no way to do this without it looking weird?
 
Hey sorry for the bump guys, but I figured it'd be better than starting a new topic all over again.
I'm working on a show right now which has a fountain on stage. As would pertain to the thread, the lighting designer wants the pool/fountain to be lit. I know that everyone's been pretty much saying to just stick with conventionals run through GFIs (question: can you run a fixture -> gfi -> dimmer? I would think so, but), but its a theater in the round and nonsubmerged fixtures might look a bit wonky on stage (and I'd be hesitant to put them underneath and enclose them, because of heat/gravity issues. Though LED fixtures would take care of the heat...)
So does anyone else have experience with underwater lights? I did some searching online and found mostly really expensive lamps designed for preexisting pools. Am I missing something, or is that really all that's out there?

Conventional GFCI's cannot be used on the output of dimmers, and will often cause problems when feeding a phase-control SCR dimming system. And let's be clear that for any voltage above 15VAC, a GFCI with a 6mA Class A trip current is required. A GFI with a trip current of 30mA or greater cannot be used for personnel protection in North America--only for equipment protection.

Leviton makes a nice device called the 36895 GFCI For Theater Dimming Systems. This can be safely used on the output of an SCR dimmer. Data sheet attached.

ETC also makes a Sensor GFCI dimmer for this type of application.

Of Course, you can avoid GFCI's on dimmers altogether by using LED fixtures with GFCI's on the input to the power supplies.

ST
 

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You can use dimmers with GFI's or GFCI's.
I'm thinking that an AFCI may also be a wise idea.

1. A normal GFCI cannot be used on the output of a dimmer.

2. Harmonics on dimmer systems will often cause GFCI's feeding them to trip. Additionally, UL requires a GFCI feeding a non-linear load like an SCR dimmer to sense peak fault current, not RMS fault current. No standard GFCI does this.

3. A GFI has a trip current of 30mA or more and cannot be used for personnel protection in North America. A GFCI with a 6mA trip current must be used.

4. See my other post regarding the Leviton "Dimmer GFCI".

5. An AFCI is for arc-fault protection in residential applications, and would not add a lot to a submersible application, even though many AFCI breakers also incorporate GFCI. For all same reasons as GFCI, AFCI cannot be used on the output of a dimmer.

ST
 
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