- Jun 30, 2009
- 30
Intellibrite Light: 12 volt vs 120 volt
- Thread starter QCJLo
- Start date
12 volt is low voltage and will need a transformer. Your existing light is most likely 120. How are you turning the one you have on now?
- Jun 30, 2009
- 30
- Nov 12, 2009
- 324
- Pool Size
- 15000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
I presume you have checked local codes...I have no choice where I live - kinda made the decision to go with the 12V Intellibrites easy.
- Jun 30, 2009
- 30
Why would I even want the 120 volt? From what I'm being told, the 12 volt is more energy efficient.
120V can run longer distances. The voltage difference was originally marketed as safer because of the lower voltages. It isn't. Current is what kills. One volt at 1 amp can kill you but 120v @ 1/120th of an amp will not. Same power available.
Added
Also, with the transformer, the GFCI then becomes isolated from the fixture and is now slower to react.
Scott
Added
Also, with the transformer, the GFCI then becomes isolated from the fixture and is now slower to react.
Scott
- May 3, 2007
- 16,828
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
I think Scott and Jason covered the main differences.
120v is more efficient
12v is safer
Although in reality even those differences should not be deal breakers. 120v are made safer with GFIs so the risk is quite small. And the amount of energy saved from a 120v over a 12v is probably not all that much and can be mitigated with larger wire. So it really comes down to which is the pool setup for or which the owner prefers. This is why manufactures offer both.
120v is more efficient
12v is safer
Although in reality even those differences should not be deal breakers. 120v are made safer with GFIs so the risk is quite small. And the amount of energy saved from a 120v over a 12v is probably not all that much and can be mitigated with larger wire. So it really comes down to which is the pool setup for or which the owner prefers. This is why manufactures offer both.
One more suggestion, a transformer adds another point of failure. They aren't ridiculously expensive but it is just one more thing to buy years down the road.
Just to add some more info on GFCI and 12 volt systems. A transformer eliminates the ability of a GFCI protection device to provide any kind of protection on the output side of the transformer. Contrary to popular belief, and despite what you may have seen on an episode of CSI, GFCI devices do not need or even use a reference to ground. They operate by actively measuring the current through the hot and neutral sides of the circuit. If a difference in current between the two exceeds 5ma, the device assumes that the difference is being caused by leakage to ground and trips off the power.
A transformer consists of two electrically isolated circuits: the primary windings (120v in this case) and the secondary windings (12v in this case). Electromagnetism creates the voltage in the secondary windings. The secondary windings are not electrically connected to the primary windings at all. The point being that you could put the exposed ends of the secondary output (12v) wires directly into your pool and the GFCI will never know about it. The current flow through the 120 volt side of the transformer will still be perfectly balanced so the GFCI will never detect any problem with the circuit.
I seem to recall reading that the NEC (National Electric Code) doesn't allow for the installation of 12 volt outdoor landscape type lighting within 10 feet of a pool for this very reason. Does anyone know if pool light manufacturers add more protection circuitry to the 12 volt side of the lighting systems to protect you from shock?
A transformer consists of two electrically isolated circuits: the primary windings (120v in this case) and the secondary windings (12v in this case). Electromagnetism creates the voltage in the secondary windings. The secondary windings are not electrically connected to the primary windings at all. The point being that you could put the exposed ends of the secondary output (12v) wires directly into your pool and the GFCI will never know about it. The current flow through the 120 volt side of the transformer will still be perfectly balanced so the GFCI will never detect any problem with the circuit.
I seem to recall reading that the NEC (National Electric Code) doesn't allow for the installation of 12 volt outdoor landscape type lighting within 10 feet of a pool for this very reason. Does anyone know if pool light manufacturers add more protection circuitry to the 12 volt side of the lighting systems to protect you from shock?
The applicable atricle in the NEC is 680 and it does allow listed low voltage "pool" lighting to be used. Don't confuse it with landscape lighting. It's a different animal and the 10' rule applies to it.
Sometimes, and in some places (not around here) they will allow low voltage lighting closer than 10', if the transformer has a ground plate between the primary and secondary wiring. That has not been allowed here for years, but may still be allowed elsewhere. Hard part is finding the box that complies!
- Nov 12, 2009
- 324
- Pool Size
- 15000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
My reading of the Intellibrite owner's manual implies the only difference is the 120V unit has the transformer/rectifier inside the niche. As someone who is neither an electrician or engineer, that someone might presume (perhaps naively) to be at greater risk if the GFCI failed to operate correctly (how many people actually do that monthly test thing?) than having a malfunction in a 12V DC circuit.
What am I missing?
What am I missing?
Mains potential 120VAC! - submerged in a pool of water?! And the only current restriction is a fat several amp circuit breaker or GFCI??! You would have to be utterly mad. I am sure there are a lot of issues surrounding the voltage drop of low safe voltages, such as 12V, but they are not that hard to solve. And even if you didnt solve the voltage drop, they dont apply to low voltage tolerant, low current LED lighting, which seems to be the prefered method of pool lighting today.
Im my book, 12V is the only solution, unless your happy with that thin sliver of glass separating you and the electric chair, or hoping that the GFCI possibly kicks in whilst you stare at the pool floor.
Steve
EDIT: Article here - might be of interest.
http://findarticles.com/p/articles/mi_m ... _n6255813/
And here; (which also helps explain why 12V at any current cannot kill anyone - let alone anyone even feel it)
http://en.allexperts.com/q/Swimming-Poo ... pool-1.htm
Im my book, 12V is the only solution, unless your happy with that thin sliver of glass separating you and the electric chair, or hoping that the GFCI possibly kicks in whilst you stare at the pool floor.
Steve
EDIT: Article here - might be of interest.
http://findarticles.com/p/articles/mi_m ... _n6255813/
And here; (which also helps explain why 12V at any current cannot kill anyone - let alone anyone even feel it)
http://en.allexperts.com/q/Swimming-Poo ... pool-1.htm
The glass lenses on pool lights is a not thin sliver It is rather thick and tempered. GFCIs do fail on occasion. This is why it is recommended that they be tested periodically.
While the human body has a relatively high resistance to the flow of electricity, you can get just as shocking a report when grabbing a rail, ladder, entering a pool at either voltage. The amount of power, based on Ohm's Law is nearly the same. The only difference is the losses that occur in the transformer. There is no such thing as a lossless transformer which is why the amount of power which is why I said the transformered system is nearly as powerful.
Diving, swimming, or jumping into an electrified pool without being grounded will not kill you unless we start talking about extremely high voltages like those found in lightning. Then all bets are off.
Touching a ground might.
Pool lights are safe.
Scott
While the human body has a relatively high resistance to the flow of electricity, you can get just as shocking a report when grabbing a rail, ladder, entering a pool at either voltage. The amount of power, based on Ohm's Law is nearly the same. The only difference is the losses that occur in the transformer. There is no such thing as a lossless transformer which is why the amount of power which is why I said the transformered system is nearly as powerful.
Diving, swimming, or jumping into an electrified pool without being grounded will not kill you unless we start talking about extremely high voltages like those found in lightning. Then all bets are off.
Touching a ground might.
Pool lights are safe.
Scott
There isn't any record of anyone actually dying from a 12v pool light. It could happen in theory, but it never has.
Modern pool lights, of any voltage, are designed so that no single point failure can cause electrocution. It typically requires three different safety systems failing before the light can be dangerous. The GFI needs to fail, the enclosure needs to fail, and the bonding system needs to fail before you can have a problem.
Modern pool lights, of any voltage, are designed so that no single point failure can cause electrocution. It typically requires three different safety systems failing before the light can be dangerous. The GFI needs to fail, the enclosure needs to fail, and the bonding system needs to fail before you can have a problem.
You need a pool rated transformer such as this one allthough it's AC not DC. Not sure what your light requires. http://www.inyopools.com/Products/02400 ... 02=1016676
A pool transformer requires a grounded shield between the primary and secondary windings. I went with the Savi Melody. It fits in a standard 1.5" return fitting but they have an adapter plate if you have a standard niche. Hard to beat the price on these so I got two for the pool, one for the spa, and one for each waterfall. But I've seen a pic from someone who only had one in a larger pool than mine and it still looked fine. http://www.poolsupplyworld.com/pool-lig ... melody.htm There are some pics in this thread; which-lights-for-my-pool-t16879.html?hilit=savi melody
A pool transformer requires a grounded shield between the primary and secondary windings. I went with the Savi Melody. It fits in a standard 1.5" return fitting but they have an adapter plate if you have a standard niche. Hard to beat the price on these so I got two for the pool, one for the spa, and one for each waterfall. But I've seen a pic from someone who only had one in a larger pool than mine and it still looked fine. http://www.poolsupplyworld.com/pool-lig ... melody.htm There are some pics in this thread; which-lights-for-my-pool-t16879.html?hilit=savi melody
QC, does warranty factor into your decision equation? For me, I was going to go with the 12v Color Intellibrite 5g LEDs but reviews on all LED lights are so poor for all manufacturers that I went with the one with the longest warranty period (SAVI Melody P.)
Most importantly from a safety point of view, except for low voltage light listed as not requiring grounding, make sure your pool builder/electrician bonds AND GROUNDS the light niche correctly.
There should be a single strand copper wire, insulated with green pvc, coming into your niche. Where it is attached should be covered with blue goop to prevent chemical corrosion where the copper meets the stainless underwater.
It seems a significant number of PB's/electricians do not do this. It is part of the NEC code for pools and, assuming you require an inspection, the inspector should check for it before you get a completion certificate.
ft.
There should be a single strand copper wire, insulated with green pvc, coming into your niche. Where it is attached should be covered with blue goop to prevent chemical corrosion where the copper meets the stainless underwater.
It seems a significant number of PB's/electricians do not do this. It is part of the NEC code for pools and, assuming you require an inspection, the inspector should check for it before you get a completion certificate.
ft.
i've been searching the forum to see people's experiences with the various LED lights out there. I want to switch out my incandescent lights with some more colorful and energy efficient LEDs. Sorry to jump in late here, but I feel like I need to clarify a few misconceptions. For reference, I am an electrical engineer with biomed engineering background. 12V, unless you have open wounds bilaterally and are the world's unluckiest fella, is not likely to kill you. You might feel a tingle, but even that is extremely unlikely. If you don't believe me, touch the terminals of your 12-14V car battery. There is some confusion about the power delivered to the light and the power delivered to the person getting shocked. Yes, the power delivered to the light is the about the same whether or not you use 12VDC or 110VAC (LEDs rarely operate over a couple of volts). However, the power delivered to you has nothing to do with the power delivered to the light. Yourresistance is what governs the amount of current you experience. V = I Rskin --> I = V / Rskin. Penetrating below the epidermis, the average resistance is about 300 ohms (hence my comment about bilateral wounds above). At 12VDC, the current would be, at most, 40mA. Sounds small, but more than enough to do you in. At 110VAC (which is actually +/- 170V, 110VAC is RMS), your max shock is 170/300 = 570mA, almost 15 times greater current. That's more than enough to burn/fry, even in water. Wet, unbroken skin, has an average resistance of 1kOhm. So 12VDC shock current would be 12mA, about twice the GFI limit. It's enough for quite a shock, and possible damage. Definitely going to feel it. For 110VAC, it would be 170mA -> still enough to cause burns AND death. SO, moral of the story, we want our stuff properly connected, grounded, and contained/sealed. So, why 110VAC instead of 12VDC? Simple, the driving force behind most contractor decisions - it's cheaper. Higher voltage, lower current, same power, thinner wires, longer runs, smaller conduit. 12VDC *IS* safer. Ideally, we want 5-6VDC systems, which would then be in line with GFI limits around 5-6mA, or a transformer demand side GFI interrupter. Personally, I'd prefer the lowest voltage possible, would like to keep it AC, as it is more efficient (thinner wires, cheaper, etc.). Of course, none of this matters if your swimming pool has TDS = 0, and is distilled water.
Anyway, sorry for the rant!
Thanks,
Mo
Anyway, sorry for the rant!
Thanks,
Mo
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