Can anyone direct me to the best information on wiring a new residence for 100% LED lighting?

I am looking for LED wiring 101 ~ What are wire gauge options, voltage regulating options and what are the things to watch out for?I understand we are still very much in a hybrid AC/DC universe and AC has to exist for kitchen appliances, and infrastructure appliances in the Utility room, however, our client wants to take the step into LED. The house is around 1600sf and one floor.
Unfortunately, I've had difficulty finding a good resource so thought I would turn to the experts here as I am also interested in hearing about any positive or negative experiences with wiring for LED and LED lighting? Thanks in advance.

Hi Ruth-

I'm also building a house and what my wife and I are doing is wiring it traditionally for 110v AC circuits and we are going to simply screw in LED bulbs everywhere. It can be that simple, with no need for hybrid AC/DC anything. It's certainly one way to go about it.

Get a copy if the electrical code,if you are a comercial builder you need one.
Off the cuff, do it the same as you would have otherwise, but when you get to specing out the fixtures , consider buying fixtures that have their LEDs  built in.
I say consider, because these are still new to the market and the warrenties are untested.

If it were me, I would plan on installing about 3 times more light sockets in the house to make up for the dim bulbs that seem to be the fad in LED lighting.

If your goal is to get the maximum efficiency, then CoB style LEDs are probably the only option. They typically run at 30V and currents between 100mA and 700mA and have efficiencies up to 150lumen/Watt (check the efficiency!).
To drive them, they need so called constant current regulators. Most of them require a higher input voltage than the LED runs at, examples would be 36V or 48V. Constant current regulators for 48V are more expensive and less common.
So I would recommend a 36V system if you want low cost/lamp and 48V if you want less expensive wires. The power supply needs to detect and turn off at a short circuit and be isolated from the mains (which makes it very safe to work with).

Here in Germany 48V (and 36V) do not fall under safety regulations, so you can work freely with them.

Wire size: Assuming a 36V system and a 20m of cable running to a 20W LED:
- The current will be 20W / 36V = 0.555A.
- The current has to travel both ways, so the effective cable length is 40m.
- The voltage drop should be below 2V (giving >34V at the current regulator)
This gives a maximum resistance of  R = Voltage / Current = 2V / 0.555A = 3.6 Ohm. (and 2V / 36V = 5.5% loss)
With 40m of cable, that gives 0.09 Ohm/meter. = 90mOhm/m. You want a wire with less than that.
AWG 24 has 80mOhm/meter, so that would be just good enough.

In practice I would probably use AWG 20 (33mOhm/m) and 48V, even if the constant current regulators are more difficult to source and somewhat more expensive.

It might be interesting for your client to build some of the lights themselves. It gives far more options and in the worst case one LED dies. All they need is: A LED, a constant current supply with a current below the LEDs maximum rating, thermally conductive glue and a heat sink capable of dissipating the power that goes into the LED without getting too hot. (50°C as a rough estimate, there will be a rating in the LEDs technical data.) Generally, running the LED at lower current and lower temperature will increase their lifetime and efficiency significantly. Oh, and a soldering iron. But again, as they this is low voltage that is insulated from the mains, there is no risk apart from damaging the LED or the constant current supply. (I have killed a few myself.)


EDIT: Two more things to watch out for are:
- Color temperature (either give them a range from 3000K, 4000K, 5000K, 6000K to try, or ask them to visit whatever store has LED lights on display) I prefer 5000K.
- Color rendering index: I have used a few ones with mediocre color rendering, they illuminate the area but colors may not appear as they are. My best LED currently has a CRI of 80, but I am going to upgrade to 95 very soon.
There are plenty of videos on youtube about both of these.

One led I will buy, and consider to be quite good. That one would require a 48V supply.

EDIT Nr. 2: In the typical case where the constant current regulator is a Buck-Converter without input capacitor, the input current is actually the same as the output current, so the above wire calculations has to be done with the LED current. (0.7A instead of 0.55A in the example.)

I'm not a "lighting specialist", but I do hold a master electrical license and I am some what familiar with this kind of lighting system.

More than anything else - LED lighting refers to the type of lamp that you will use, in place of other lamps that are available (incandescent, fluorescent, halogen, etc). For normal residential lighting needs, wiring your home in compliance with NEC (National Electrical Code) and local building codes will provide you with everything you will need to install LED lighting. Nothing needs to be done any differently.

Having said that - there is the potential for "flickering". Electrical power in the US operates at 60 hz (AC, or alternating current), which means that the electrical current is pulsing at a frequency of 60 cycles per second. That pulse can be recognized by some people who are sensitive to those sorts of things, and has been known to cause headaches and other health problems (epileptic seizures), and (by extension) there may be a potential risk from long term exposure. All lamps flicker to some degree (the result of 60 hz cycling) - but LED lamps are affected more than other types of lamps. Incandescent is the least affected. Not trying to scare anyone, just offering "published" information so you can make informed choices.  

There are electronic devices that can be installed, designed to increase the frequency of the power to as much as 150 hz. The higher frequency reduces the noticeable flicker. Another expense, but better than dealing with any ill affects from lighting you will use in your home for hours a day - everyday.  For more reading - Flickering

And there are a few other things worth considering - depending on what someone perceives their personal lighting requirement to be.  Generally speaking, LEDs emit light that could be described as bright, cold, and directional. So, thought should be given to perhaps using more than one lamp in the ceiling of a room, to reduce the stark shadows. Using a defuser over the lamp will keep it out of direct line of sight. Of course, table lamps could serve the same purpose.

You will want to also consider the color spectrum of the lamp you are purchasing. There are benefits from having one color verses another. Color

LED lamps aren't cheap, but very energy efficient. All things being equal, they should out live other types of lamps. And if all that is true, then there is definitely a pay back in energy costs over the life of use.  But - because they cost so much and last so long, make sure you know what you really want to satisfy your needs up front, before you make the purchase.

Hope that helps answer your questions.

Hi Ruth, if I can read into your question a bit more, I "think" you might be wondering about using smaller wire gauge in your wiring circuit since LEDs don't draw much current.  I've wondered if some day they will change the electrical code in the US to allow for smaller wires on lighting circuits.  But for now, as far as I know, lighting circuits still need to use wire sized to handle incandescent sized loads.  Typically 15 amp circuits with 14 gauge wire.

Mike Jay wrote:Hi Ruth, if I can read into your question a bit more, I "think" you might be wondering about using smaller wire gauge in your wiring circuit since LEDs don't draw much current.  I've wondered if some day they will change the electrical code in the US to allow for smaller wires on lighting circuits.  But for now, as far as I know, lighting circuits still need to use wire sized to handle incandescent sized loads.  Typically 15 amp circuits with 14 gauge wire.

No argument - but in order to avoid any confusion - the code does not differentiate between the types of lamps used on a circuit. It is written to address the combined amperage of the connected load - regardless of what that load might be.  For that reason, it is not very likely that the code will be changed to accomodate "LED only" circuits. The savings would not be that dramatic anyway - be safe.

You are correct 14 AWG is the minimum size conductor allowed under the NEC for residential lighting circuits. And - although the wire (copper) itself is able to carry a 20 amp load safely (when installed correctly) - the NEC requires that 14 AWG be protected from loads over 15 amps.

It should be noted - technically speaking - a continuous load connected to a "regular" 15 amp circuit breaker should be limited to a total connected load of only 12 amps, and not 15.  A normal 15 amp breaker is not designed to carry a full 15 amp load continuously. What is continuous?  Anything that would normally be used more than 3 hours at a time (NEC). Reality check: how often do you figure to have all of your lights on at the same time for more than 3 hours?   Some?  ....yes.   All?  ...not likely.   Some will interpret what the NEC says on this issue to be limited to a single cord connected appliance being limited to 12 amps on a 15 amp circuit breaker. Others would argue that it is the combined load on the circuit - and is intended to accomodate and account for motor loads when starting (like ceiling fans, attic fans, etc.). Motors will start at 125% of their full load current.   BUT - you can purchase "fully rated circuit breakers" (at a premium) and "load it up to the max".

Regardless, it is a good / safe practice, when designing your circuit layouts, to keep those things in mind.

Thanks Tony!  Now that I re-read my post I should've said "I've wondered if some day they will change the electrical code in the US to allow for smaller wires on LED only lighting circuits."

I'd imagine that some day in the future, when maybe everyone is using LEDs, they'd come up with a light bulb socket that is only for LEDs and then if you put in a fixture that is only for that socket, then you could wire the lighting circuit with much thinner wire.  But I doubt that will be in the next 20 years.

I hope our family here finds this information useful:

It is important for us to understand that any fixture that could be initially installed, could - at any time - be replaced with any other type of fixture available on the market. So to me, that means the type of socket used for any lamp is irrelevant when it comes to how an electrical circuit is installed.

For those kinds of reasons - the National Electrical Code was written and published in an effort to establish minimum industry standards as an appropriate step to provide for public safety. It has established minimum standards for all different types of electrical installations, so manufacturers, designers/engineers, installers, and maintainers of those systems could all be aware of what can reasonably be expected in locations that have adopted those standards. And when the public understands that a standard that has been enforced during construction - it offers the public some level of confidence in the safety of the wiring systems installed in your home, your work place, at the hospital, airport, restaurants, etc.

As an example: Arc fault breakers (GFIC), Ground fault interrupter type circuit breakers can be a nuisance and they certainly are more expensive than a regular breaker (and LED lamps are a lot more expensive than incandescent lamps). But I know from personal experience, they save lives. And I know from personal knowledge that there have been lives lost and others seriously injured when they weren't used. Are they necessary?  Well, you don't need it, until you need it - and when you need it, then you are so very thankful that you were protected.

And while it is true that any electrical circuit can be connected to any size wire smaller than #14 AWG, in order for that wiring system to be safe it would need to be protected with the appropriate sized fuse for that wire size. Anything smaller than #14 AWG would need to be protected with an overcurrent protection device rated for less ampacity accordingly. That way - if you decide to run your 2000 watt appliance on #16 AWG wiring, the OCPD will open the circuit before you burn up your wiring and maybe save your home and family.

My life has been spent working in the electrical field - in a lot of different positions. I have known people who sat on that board. The people who are responsible for writing and approving those regulations are folks that include labor (electricians) and business (contractors). They make decisions as a collaborative effort. The basis for all of the decisions for what gets written into the code are made with public safety at the center. How many members make up that board? There are no less than 13 pages (8-1/2" X 11") full of names that sit on 14 different "Code-Making Panels" that can be found in the front pages of any code book. Anyone who recognizes a need for an existing regulation to be revised - or the need for a new regulation can submit their recommendation for review. The NEC board is not part of any federal, state, or local government. It is organized under the National Fire Protection Agency (NFPA). The NEC is not a federal regulation. The NEC is only enforced in locations where it has been adopted into law by state legislative branches of government.  States are not required to adopt the current edition or standard. I don't know why they would, but... I imagine that a state could repeal the law that adopted the regulations - if they chose to do so.

All of that being said - it should be obvious that there is no profit motive for these folks. They have volunteered their services for the good of the public.

I would consider "low voltage" DC installations for lighting the future. Possibly with two additional data wires to allow switching and dimming over a bus, without having to route the power cables over the switch.
DC is much easier to work with in electronics, there is always power available, unlike in AC where power needs to be stored for 10ms (a long time in electronics, modern regulators go up to the MHz range).

All that remains is to figure out the voltage, connector and data protocol…

Sebastian Köln wrote:I would consider "low voltage" DC installations for lighting the future. Possibly with two additional data wires to allow switching and dimming over a bus, without having to route the power cables over the switch.
DC is much easier to work with in electronics, there is always power available, unlike in AC where power needs to be stored for 10ms (a long time in electronics, modern regulators go up to the MHz range).

All that remains is to figure out the voltage, connector and data protocol…

You have some good ideas. I think the biggest problem for the "public" would be the cost of setting up the infrastructure to generate a second source of energy, and the distribution equipment and transmission lines necessary to get the DC power to the "public". A huge expense - just to provide for a certain type of lighting.

Public utility wind and solar power generation (DC) is becoming more common, but currently - it is set up to provide AC for the existing grid. But I agree, there are some very good reasons for considering DC.  

I am a big fan of a "private individual" option - where the end user is allowed to provide their own DC power source. The NEC has already made provisions for solar and wind power generation and wiring systems connected to it. If everyone were generating their own power, we could collective elect to be connected to a DC grid (no need to syncronize output with DC) - and create a de-centralized power source for the public. Or, generate DC for home use, and convert any surplus to AC for a sell back to the utility on the existing grid (already being done by some folks).  But unless you are installing a really substantial system - it could take a life time to realize a pay back (if that was the goal).

I'm not sure how practical it would be to eliminate AC power. Certainly,there would be a lot of resistance (pun intended) from folks who would lose their jobs as a result, and from folks who would end up with obsolete appliances and equipment.

It's also worth noting that, unless the voltage level is high enough, any equivalent connected loads (wattage) would require larger conductor sizes (current). example: 120v x 2500w = 12a load would use #14AWG; and 24v x 2500w = 60a load would use #6AWG. Big difference.

Just shining light in dark places where things are sometimes hidden.

I'll stop now. This isn't my thread and it could be said that we have drifted away from the original question.

Might make an interesting separate thread though.

The general contractor should hire a liscenced and insured electrical contractor for this new construction. If you are a general contractor, unliscenced employee/worker, or some type of subcontractor, then don't touch your clients electrical installation. It will cost your client less to have it installed professionally, safely, and legally from the beginning. No reason to accidentally burn down a structure just to try to save a buck. There is a reason it takes a decade of trade experience and a hard test before someone can become an master electrical contractor. Likewise, your client can hire a professional lighting designer, or architect or electrical engineer if they wish.

Anyone with some basic understanding of electricity can wire a low voltage DC installation. The one critical component is the power supply that converts AC into DC, but that can be connected into a regular outlet, if one doesn't want to touch the AC installation.
I have installed a 48V, 100W power supply that is insulated from the mains and shuts off if it is overloaded. Starting a fire with that would require intentionally placing a 25Ohm high power resistor (not just wire) in a combustible piece of insulation.

I am well aware that the "professional electricians" are interested in keeping people from fixing their installations, but that doesn't necessarily improve the quality of the installation, nor does it make it cost effective.

But sure, if someone wants to burn a lot of money, hiring an architect, lighting designer, electrical engineer, DC electrician and AC electrician, is a good way to do so.

If your client wants LED lighting for their new construction of a 1600 ft2 residence, this installation should empower their financial investment in building a new home, not jeopardize it.


This means that the electrical work should:

1) Be legally permitted and inspected. In most localities, a homeowner may pull a homeowner permit and perform the work themselves. But the homeowner is not here asking these questions themselves. Without permitted and inspected work, client would be hard pressed to have a mortgage, insurance, certificate of occupancy, or resell the house.

2) Should enhance their investment and not jeopardize it. It is standard and expected in the said client's NY State real estate market, for homes to be equipped with lighting (or lighting branch circuits) wired with 120V AC. LED lighting fed with AC power is the norm in new construction, many good UL listed options exist affordably on the market. Even if the client wants LV DC wiring powering their fixtures (hey it's their house, their money), and there are non-lighting branch circuits being wired in AC, then I suggest to include a full AC lighting installation, so that their investment is not trashed. The added cost of some 14ga when the wire is already being strung is not much. Nothing more wasteful than tearing out drywall on a perfectly good house--or investing (burning) huge sums of money on constructing a new house, while killing one's potential resale with a few tightwad quirks.
If I was to bid on buying a house that only had LV lighting wiring in place, that would provide me great leveraging on the asking price. There is a place for LV DC wiring, including lighting, but I don't see advantages using it in a new residence these days with abundant cheap AC LED fixtures and bulbs, including even low budget off grid electrical systems.

You could also wire with cat6 right along side traditional wiring. It is inexpensive, allows data for all kinds of purposes and would be in place for selection or later adoption of Power over ethernet office, communications, lighting and smart home integration that looks to be coming.

The wire is cheap, power supplies inexpensive and data and automation is a possible aside from raw power.

You could selectively place the circuit where it makes sense or is requested.

This is able to be done and being done in a code compliant manner.

https://planetechusa.com/blog/poe-lighting-how-poe-is-revolutionizing-led-lights-in-smart-homes-and-offices/

Hi All,

I wanted to point out the LEDs are bad for your eyes. Not trying to be annoying just confused as to why I am of the few who notice how harsh this light is. LEDs emit a high amount of blue light which creates sleep disorders, vision disorders etc.

Here are some articles on it:



https://www.washingtonpost.com/national/health-science/some-cities-are-taking-another-look-at-led-lighting-after-ama-warning/2016/09/21/98779568-7c3d-11e6-bd86-b7bbd53d2b5d_story.html


https://articles.mercola.com/sites/articles/archive/2016/10/23/near-infrared-led-lighting.aspx

LEDs not good for you but possibly some with the amber color variation better.

I just want everyone to be healthy.

B Callender wrote:I wanted to point out the LEDs are bad for your eyes. Not trying to be annoying just confused as to why I am of the few who notice how harsh this light is. LEDs emit a high amount of blue light which creates sleep disorders, vision disorders etc.

LEDs make powerful light up to the blue part readily available. I do not disagree that illuminating the streets at night with bright cold white LEDs may not be the smartest idea. (Mercury lights are not better here.)

But that is no argument against LEDs. The argument they make is that too much blue light at the wrong time isn't helpful.

And yes, powerful LEDs are bright and looking into them isn't pleasant. But do you look directly at the sun too?

I would also like to point out that in cloudy climates, powerful lights are needed to work without getting tired.

–––
Frank, powering LEDs with Power over Ethernet is indeed interesting. But it isn't nearly an ideal solution. PoE is limited in Power by the wires used (which are made for signals, not power). It also requires rather expensive cables. A Cat 5? cable contains 4 pairs of wires, each pair with its own shielding and the whole pack shielded again. But LEDs only need power and a little data, so the complex wire is a total overkill at the data speed side (which requires expensive controllers at the LED and dimmer), and has too much resistance for an efficient power use. All that can be done is to increase the voltage (currently around 48V), or use thicker wires which are more expensive.
I think it makes more sense to use PoE where a lot of data is needed without high power demands.

I am currently working on my own LED controller (up to 80V input voltage, 2A output) that can be controlled digitally via a thin pair of wires that connect to the switches (with brightness control). This keeps power and data separate and makes the electronics a lot less expensive (~10kb/s vs. 10Gb/s and 5V vs. 48V).

Here are some great industry sources. They include installer/contractor, university study and cover code and practical use along with control, data, power transmission and electronics and code issues.

https://www.google.com/amp/s/www.belden.com/blog/digital-building/3-reasons-why-power-over-ethernet-demands-cat-6a-cable%3fhs_amp=true

http://www.ledsmagazine.com/articles/print/volume-12/issue-8/features/dc-grid/poe-technology-for-led-lighting-delivers-benefits-beyond-efficiency.html


From;

https://www.ecmag.com/section/systems/power-poe

"Goodman said that, through PoE, contractors will also benefit from a far less-complex installation process, especially in areas where fixtures are difficult to access." 


It does not require an electrician, takes advantage of off the shelf components and can feature software enhanced communication/automation.

It lends itself well to having a home network control or as basic as manual switches, or with processors and optional internet connectivity. If you can plug in an ethernet cable, and better if you can terminate inexpensive cable (1000' box of indoor or outdoor rated cat6 is usually the least expensive wire in a homerun on our installs with distant arrays and most system monitoring and control such as rapid shutdown.), then most people can do it themselves and it can make for a highly controlable and safe installation.

Additionally, if the work is being done to integrate automation control and monitoring and such by a data-com company or tech, then it will be a smooth integration and bugs can be shook off (tech assistance), permiting and other co-ordination, by a home owner or contractor is reduced.

As far as high efficiency, we have found that 90w of decent led light is fine for our kitchen use. We use a spectrum that we like and non ideal directivity, so we would have higher usable lighting levels with the same or possibly fewer watts total, if the diodes were not arranged omnidirectionally in screw in replacement led lamp/fixture combinations.... in our case.

For off grid use and for micro homes or rv/marine, this makes sense as most of my points of use will not exceed the 100 feet and 150w, 48v (double check, pretty sure i read that there are people looking to have allowance and technique for it) for safety and performance. Network switches, injectors, and leds are widely available and fixtures are catching up with troffer fixtures that are a replacement for 4x t-8 lighting for instance.

http://www2.cree.com/smartcast-landing-page

http://www.lighting.philips.com/main/prof/indoor-luminaires/downlights/luxspace/luxspace-poe

Its been a while, but i usually check ever 3-4 months for what is being offered.

This way certain people can have the few ac (and/or) receptacles or no recepticles and few hardwired connections or no hardwire connections....even batteries are available with connectors if you like and some may wire cat6a right alongside traditional ac wiring everywhere it goes, so automation, control and monitoring can take advantage of lighting and power distribution junction and outlet/inlet enclosures for gadgetry as it becomes available. That is my slant anyway.

This is going to happen unless wireless overtakes the method for most of this entertainment/office/communications/lighting, personal and small electronics, even refrigeration could be done with P.O.E.. , some water pumps and many circulators run in this power range and there is nothing wrong with parallel cabling from a networked

I expect a next level standard and one step up in wire and switch dimensions could evolve, but this is being done in large office and building environments all over the world as a trial and transition for several years no.

You can have any color or power modulation at any point of light or other use you want and have sophisticated control of loads for automated maximization of power usage and power availability response by every point of use or appliance, now, today and on a diy equipment group and homestew or community software development or turnkey solutions.

Monitoring of power use at any point!

I am interested! Some others may be too. Electricians can crosstrain and bring in IT/network techs, we do as RE installers and many outfits for security monitoring and safety data-com already do, at a higher level.

Thanks to recent advancements in both PoE and LED technology, these lighting systems—which are increasingly popular among building owners—have become the newest candidates for the PoE platform.


“Traditionally, buildings have had to run 120V or 227V power to support conventional high-voltage lighting systems involving fluorescent technology, which required junction boxes, relay panels, cables, conduit, and many other components,” Sekinger said. “But, as PoE systems have evolved to support 60W of power today, and LED systems have become increasingly efficient—for example, many LED troffer configurations that consumed 40–50W two years ago require just 30–35W today—LED lighting is a low-voltage system that’s now fully able to benefit from the power of PoE.”


http://www.electronicdesign.com/power/poe-max-power-pushes-60-w-and-beyond

Fun stuff.

tony elder wrote:I'm not a "lighting specialist", but I do hold a master electrical license and I am some what familiar with this kind of lighting system.

More than anything else - LED lighting refers to the type of lamp that you will use, in place of other lamps that are available (incandescent, fluorescent, halogen, etc). For normal residential lighting needs, wiring your home in compliance with NEC (National Electrical Code) and local building codes will provide you with everything you will need to install LED lighting. Nothing needs to be done any differently.

I agree, while the wiring specified by the electrical code might be overkill for LED lighting, chances are you will never get an code variance approved.  If you try to save a little money using under size wires, the inspector will just make you tear it all out and replace it with wiring that meets the code.

tony elder wrote:
Having said that - there is the potential for "flickering". ...
There are electronic devices that can be installed, designed to increase the frequency of the power to as much as 150 hz. The higher frequency reduces the noticeable flicker.

Another, possibly more affordable, option would be to run the lighting on DC.  This is especially true for folks who are off-grid and already have DC power available.
As long as the maximum DC voltage is below 60V you don't have to take any special precautions over typical AC wiring.
The Square-D QO line of circuit breakers are UL listed for up to 60V DC, and while they can be somewhat difficult to find, there are 'standard' light switches available that are UL listed for use on DC circuits.

I have an old Eagle model 777V-BOX  switch that is DC rated for 10 amps at 125V, I don't think they are made anymore.  Eagle 901V-BOX and 903V-BOX are also AC/DC rated.

I think Pass and Seymore still make wall switches rated for 24V DC.

Couldn't you have two different circuits. One circuit AC/DC 240v (uk)  and whatever the norm is for the USA,  for the normal items like TV,  washing machines etc and a 12v DC run off deep cell batteries for the lighting using car LED's which are really bright but don't use that much voltage and have an inverter to allow you to use the DC power as AC/DC if you're using a lot of 240v. That's what I'm thinking of doing if I can do a low impact build. It will take a lot of power usage away from grid use especially at night when most people don't tend to have much running. Just a thought.

Lets be frank. New York has stringent electrical codes. ALWAYS for the health and safety of others USE THE NEWEST CODES and Regulations. Local inspectors love to see people go to code. We have electrical codes for a reason. The reason,...the dead bodies of adults, children, animals and destroyed property.

The latest LED still uses amps/watts/voltage. Enough to easily kill and destroy. It is this simple. Even here on the family farms where we can do things differently in some respects, we still strive for code. It does not cost more and is safe. Its that simple. If electrical is to code, you cant get sued either.

In my residential I insist on 12 gauge still in typical 15/20 amp circuts. Why? Wires over burdened will get hot. They get warm during normal use. Especially in certain weather conditions. I would rather have the safe factor! I insist on top grade circuit panels also. Why? There are vast differences between builder grade and best grade electrical panels. It does not cost that much to have better wires, electrical panels, new drops and fixtures appropriate for the situation.

Also, most LED lights and fixtures are made good enough to work.....good enough...means you must be better.

Now for the kicker.

If you are considering low voltage remember it still can kill you. Use appropriately. There is code for low voltage and different applications.

Wire if for a lifetime and the next person who will live in the situation. Talk to your local inspectors and get a good rep. Get coded. Get it right. Good luck.

many ideas have been commented about here   remember the actual amperage draw on LED is tiny.   A cob is a set of 5 led emitters on one base.   If you have a light that draws 9 watts this is a tiny amount of power.  1 amp times 120 volts=12 watts so in essence you could run 12 light fixtures per circuit.  Talk about daylight in the room. That is = to having 12    60 watt incandecent bulbs turned on.   How often do you plan to do that LOL     Just a for home use in living room and bedroom you may wish to go to a warmer > yellow bulb  meaning perhaps 3000 or 3500 kelvin    It is really nice to go with daylight in bathrooms and kitchens so you can actually see the real colors

I've also been looking at this problem for an off-grid property with a very small inverter. LED does away with the need for heavy duty and short-as-possible cable runs for 12V lighting systems.
Here in New Zealand the specialist lighting shops are full of LED fittings, but they are all designed for mains (240VAC) operation with built in transformers and rectifiers.
The only DC fittings I have found are from caravan and yacht suppliers, and hence tend to be expensive (the old saw about a yacht being a hole in the water into which you pour money).
The other problem with them is that caravans and boats tend to have low ceilings - so most of these fittings have switches on the side of the fitting, which will be out of reach in our house application.
Yes we can have MR16 bases dangling on wires, but we'd prefer something a bit more elegant!  And otherwise unconstrained LED spots do occasionally fall out of those bases when hung vertically.

Christopher Steen wrote:There is a place for LV DC wiring, including lighting, but I don't see advantages using it in a new residence these days with abundant cheap AC LED fixtures and bulbs, including even low budget off grid electrical systems.

I see an advantage (in the off-grid situation) - inverters trip out, and unless they are very fancy and expensive, they don't self-reset. Having your lights still working independently when the inverter trips is definitely a good thing™

Please remember that having too much LED light in your life destroys your macula and WILL eventually make you blind.

CFLs not only have mercury, less light than incandescents, don't last as long as advertised - but they have a deep blue spectrum. Using this at night fakes your body into thinking it is still daylight out - and so your melatonin and sleep cycle becomes disrupted.

The light CLOSEST to actual sunlight IS the incandescent. So-called "full spectrum" and grow lights miss significant portions of the light spectrum (worse than incandescents) and have huge spikes at other frequencies. Look up Dinshah...

Use them of course, in moderation - but keep yourself in the sun because i think we are humanly solar powered to greater degree than we'd thought.

Where is the evidence too much LED will send you blind, please?

brad roon wrote:Please remember that having too much LED light in your life destroys your macula and WILL eventually make you blind.

CFLs not only have mercury, less light than incandescents, don't last as long as advertised - but they have a deep blue spectrum. Using this at night fakes your body into thinking it is still daylight out - and so your melatonin and sleep cycle becomes disrupted.

The light CLOSEST to actual sunlight IS the incandescent. So-called "full spectrum" and grow lights miss significant portions of the light spectrum (worse than incandescents) and have huge spikes at other frequencies. Look up Dinshah...

Use them of course, in moderation - but keep yourself in the sun because i think we are humanly solar powered to greater degree than we'd thought.

Where do people get this nonsense?  That doesn't even make sense from either a biological or physical point of view.  Light is light, doesn't matter to the human body how it's generated.

The amount of mercury in a CFL is less than the amount in a large can of Tuna and people don't eat the lights.

ANY light at night can mess up you circadian rhythm, the problem with blue light is from using blue leds WHILE your sleeping, like from a night light or a clock radio etc.  Even incandescent lights also put out blue light, and green, and yellow, and purple, etc.

Full spectrum lights are DESIGNED to only put out light at certain frequencies, specifically the frequencies used by plants for photosynthesis.  The idea behind them is to not waste energy producing light that only get's reflected off the leaves and not absorbed anyway.  

Henry - so to you, UV-A is UV-B and UV - C.  It also isn't different from infrared. Let's just think a little bit. Of course i'm coming from advantage here in having read "FOUR ARGUMENTS AGAINST TELEVISION" by Jerry Mander in the 80. In that book, at one point he talks about a former banker named Melvin Ott who had his little desk lamp flourescent bulb die out. It was over a plant he kept on his desk. The only bulb his secretary could find to fit that lamp quickly, was a pink fluorescent bulb. Mr Ott noticed over the next weeks and months that the plant grew differently in that light. It actually grew out and away from the light source. He found this so fascinating he eventually quit banking and studied light.

He has been given honorary degrees for some of his findings. For example, there is a strain of lab mouse designed to develop cancer quickly, and when grown under pink fluorescent light, it's tail drops off and it gets cancer. Not under regular fluorescent lights. He found that children in schools under coolwhite fluorescent tubes have a much higher incidnece of ADD/ADHD.

In the Civil War an American doctor from the north did healing with colored glass through sunlight. That was taken much further by a NY City police airplane pilot named Dinshah. He developed Spectro-Chrome light healing system which has been used to heal people "impossibly". In the 1920s one little girl with 2nd degree burns over her torso and down her legs had a specific light spectrum used on her, and she ended up not only surviving (treatment of the day was lock them somewhere quiet and let them die with morphine) She ended up not only surviving, but surviving without scars.

Today they are using specific laser light frequencies to repair some damage in the macula, there are K-class lasers which penetrate skin and heal wounds and over time, repair arthritic issues.

But, light is light. So why don't you light your home with lasers? Or fire. Same thing.

Brad, lighting a room with lasers is definitely possible (but not exactly efficient).

As someone who has spend a few years in laser physics, I can assure you that light is not as simple as it appears.
There is frequency (or photon energy or color), coherence (laser vs. lamp), modulation (modern LED dimming), bandwidth (very small: laser, small: singe color led, wide: LED with high CRI, very wide: incandescent lamp).

Why light the room with LEDs (and not incandescent, fluorescent, laser, fire):
- energy efficiency (most might output for a given power)
- color accuracy (the ability to see colors the same way as they appear in sunlight)
- luminosity (enough light to see details without needing a torch with you)
- no UV part (which "wastes energy" and risks getting a sunburn; however there are UV-LEDs if one does want UV light)

brad roon wrote:Henry - so to you, UV-A is UV-B and UV - C.  It also isn't different from infrared.

Fair enough, Natural sunlight is full of UV and IR light.
LED lights produce virtually zero UV and very little IR.

So are you claiming that LEDs destroy your macular because the they lack UV light?

My point was that blue light is the same as blue light regardless of the source.  The only difference between the light from an LED vs sunlight is that the LED has MUCH LESS of the harmful frequencies.

And actually, incandescent light is heavily weighted towards the IR end of the spectrum.  Even though it looks more like sunlight to most humans, it’s actually less like sunlight, from a spectral point of view.

I've been seeing this option popping up in some homes I've been working on.  It is an inverter and allows dimming.  Basically, you run an AC wire in and then run small wires (DC) out to LED tape.  It is essentially an off-the-shelf option.  I've seen them in two homes here in North Carolina.  This or something like it may be the ticket if you are using standard AC wiring.  The examples I have seen have quite a few DC wires going out to lighting from the single AC wire in.

James Freyr wrote:Hi Ruth-

I'm also building a house and what my wife and I are doing is wiring it traditionally for 110v AC circuits and we are going to simply screw in LED bulbs everywhere. It can be that simple, with no need for hybrid AC/DC anything. It's certainly one way to go about it.

Screwing in a "not really conventional" LED bulb that screws into an AC lamp base is not very great at all.  You are paying extra to get AC, then convert it at each bulb to DC, just for the privilege of lighting an LED bulb that would normally need DC only.  We've been duped long enough.  You can wire a house for an LED, 12V system, taking into account all you intend to light up, figure your amperage, and your length of run, to get out the wire size charts and get it right.  This is a nice job for an electrical engineer, or a good electronic tech.  It's a matter of figuring all your requirements and building the system for 20% more than you need.

We are also planning on all LED.  Being off-grid with limited power capacity, we were actually planning on installing something similar to what is in an RV.  I don't know a whole lot about building code, but I also know it's hardly likely an inspector will ever have reason to set foot there... part of the reason we're building there in the first place.  I don't want to have a massively overbuilt system powering lights with circuit boards built into them that reduce the power enough to not fry the LED I need to make light.  It doesn't make any sense, when the amount of power I actually need to draw for that light could come from a couple of AA batteries just as easily.  So why not wire for that, instead of for a bunch of appliances and heat-producing lights I don't intend to use?

I guess I should add that luckily my partner knows a lot more about this stuff than I do!  We have talked about having two separate grids like what was mentioned above; one for the lights alone, and one for other things.

You're exactly correct Norma.  LED's work on just a few volts, they're about the only thing that does work well on low voltage.

This is an older thread but I just saw it. I believe in building for future wants and needs but starting conventional. There are countless variations of LED fixtures and retrofits at this point designed around conventional AC which has made the fixtures durable and fairly cheap. Yes you run into some power loss due to converting to a lower voltage but its usually less power loss then you suffer from moving low voltage power longer distances. By Doing that you do not run into any of the code problems about non compliant switches, boxes not rated for DC,  uncertified bulbs, and poor quality control that is common in the consumer product world of low voltage LED.  Having said all that if you are wiring a home with an eye towards the future making sure all the lighting circuits remain separate in the main board is a good starting point. Should the tech catch up to aspirations separating out those circuits becomes easy. We wired in dedicated 12 volt plugs into key parts of the home when we initially built which was completely code compliant as long as you used a different plug variation not used anywhere else in the house. I originally ran all the lights on 12 volts but found the quality of the bulbs at the time so bad I installed a small inverter to the lighting circuits and switched to ac clf bulbs. Today that would be ac led bulbs instead. The damn cfl refuse to die though so there are a few stragglers left around the house over 12 years old. Those 12 volt circuits remain unused as the inverter world changed and they became much more efficient and the price of solar panels dropped so the losses to an inverter became negligible. For tiny homes or dc only situations different rules would apply. I would focus on 24 volts myself as there are a lot of commercial LED tech heading that way.  As to the poster above technically all electrical systems in ontario in homes must be ESA inspected regardless of township status... Its a big province though and enforcement is rare in very rural areas.
Cheers,   David