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46

Some light switches run a small amount of current through the bulbs even when off, usually to power small devices at the switch like a timer, motion sensor, or night light. Do your switches have either of those features, or something else like that? The way those devices work is instead of having a hot/neutral pair powering the switch, they just sit inline ...


38

Yes. The fixture is concerned with heat. Your LED light bulb makes about 9 watts of heat. Your fixture is rated for a bulb that makes 40 watts of heat. With an incandescent bulb, 98-99% of its wattage turns directly into heat. Even LEDs, 90% of their wattage turns into heat. For thermal planning, it's not worth pulling out the calculator. You're "close ...


32

Yes, it is because of the heat buildup in enclosed fixtures, and no you should not use the bulb in that ceiling fixture you listed unless you are willing to accept shortened bulb life. Your options are: Use the bulb in that fixture anyway and accept that they may burn out or dim prematurely Get LED bulbs that are approved for enclosed fixtures, e.g. many ...


25

Using these RGB as a base example Basic Electronics Crash Course Volts * Amps = Watts Watts / Volt = Amps General Information These strips indeed usually come in lengths of 5 meters but you find suppliers that will give you 10/15/20 metres options also. Most only provide 5 meters because of the power they need to power up properly. So they try and sell ...


25

You've probably connected one of the 2 power wires to the incorrect traveler terminal on the switch. This switch can be used as both a standard two-way switch as well as a three-way switch. (A three-way switch is used when there are 2 switches controlling the same device.) In standard two-way arrangement, one of the power wires should be attached to the ...


21

Most LED bulbs on the market are in fact dimmable, IF you use a CFL/LED dimmer. Your "standard" dial or track dimmer is either just a big potentiometer or Rheostat that reduces voltage through resistance, or a slightly more efficient design called a TRIAC dimmer, which uses a specialized transistor design to attenuate the line voltage by turning the line on ...


20

SHORT ANSWER: NO PROBLEM LONG ANSWER: The maximum wattage limits are largely a function of heat. For incandescent lights, more wattage means more heat. And too much of a heat buildup could result in shorter bulb life and even risk of fire, especially in a fixture in which the bulbs are fully enclosed. While lighting has traditionally been sold by wattage, ...


19

Even if LED or even CFL bulbs create far less waste heat than a conventional lightbulb, they react far more adversely to the heating resulting from ANY waste heat. A lightbulb won't care if it is in an ambient temperature of 500°F, actually it will run more efficiently - anything with electronics in it is hard to make in a way that it will survive long in ...


18

The specs are out there, just not always so easy to find. For example, one Philips Hue is rated at 9.5W with max. standby of 0.2W. (Click "The bulb" on the right side under Technical Specifications). Using this bulb as an example, if it actually uses the full 0.2W all the time, 18H x 365D x 0.2W = 1,314 Wh per year. If your electricity costs 0.10/kWh, that'...


17

I found the answer! @diceless set me on the right track in looking at where the foot of the bulb is connecting to the fixture. Since it was an older fixture (installed in the 80's, I think), the hot contact (Number 1 in this diagram ) was bent down, and it was connecting with the smaller bulb but not the bigger LED bulb. With the circuit turned off at the ...


14

Due to the lack of adequate answers, I decided to research the differences myself and provide an answer to the benefit of the community. PAR Type Lamps From a build quality and light control standpoint, PAR type lamps are generally considered superior. The explicit parabolic nature of the reflector means light is more precisely reflected directly out of ...


14

However, if I only turn off the lights breaker, and go into the switch panel with my voltmeter, I am still detecting 100V AC across the switch (with it off), even though the lights stay off when I turn the switch on. … Can anyone tell me what might be going on? Coupling between wires (inductance and capacitance in parallel wires). You say you have strange ...


13

I called Philips about this issue. They said that it indicates that the bulb is broken and needs to be replaced. Some LED bulbs have enough electronics in them that they are able to have diagnostic circuits and to report errors in this manner.


10

I was not able to find any sections in NEC that prohibit switches from being installed in closets, so until somebody can point to a specific section I'd say it's not a problem. There may be adaptations to the code in your local area, so you'll have to check with the local Electrical Inspector to be absolutely sure. The NEC does, however, have a section on ...


10

PAR = Parabolic Aluminized Reflector. The number is the diameter of the bulb times 8, so divide by 8 to get its diameter. Thus, a PAR30 is a 3.75" diameter bulb. Our last house had PAR30 floods in track lighting in the living room (a style that was all the rage when the house was built in the 1980s). You can use them indoors. The quality of light you get ...


10

Are these the the type of motion sensors which use the neutral wire? A motion sensor needs power to work. Ideally it gets always-hot, and neutral, and then provides a switched-hot to the target bulb. Such a unit should work fine, I use them widely. However some motion sensors are designed like old school dimmers - they are designed to work in old-style "...


9

You won't be able to shock yourself with 12v, but you can shock yourself with whatever power supply you find that'll do 5A at 12v. Assuming you'll only use one strip at 6a just grab a laptop power supply (I'd recommend this one: http://www.newegg.com/Product/Product.aspx?Item=N82E16812203037) - that way you really don't need to worry about whatever ...


9

The first problem here is the "100W" claim, which you here treat as the reference standard from which to compare. Actually, it's the most dubious claim of the bunch, and has never been reliable. I suspect it's a common mistake for people to fixate on the "100W" number since it's a unit they're familiar with, and that's why manufacturers toss it on the box. ...


8

By creating a project box to store the connections you will be fine. The project box will need adequate heat dispersion capabilities because the drivers for LED's are what gives off the most heat. It is imposible for the lights to catch on fire since they give off such a low level of heat that it is unnoticeable.


8

The two differences are Cost It can be dimmed with a standard dimmer A standard dimmer reduces the RMS voltage going to a light to dim it; this may be done by a simple resistor or by chopping of the top of the waveform. So a dimmable LED lamp must be able to: Cope with a big range of input voltage including part formed sine waves, which isn't easy for ...


8

Say your electrical bill is $100 a month. Now say you have a refrigerator, a computer, a window fan and your light bulbs in your house as your only electrical devices. Everything but your light bulbs are on 24/7. Fridge: 725W **NOTE MOST FRIDGES DON'T ACTUALLY RUN 24/7 THIS IS JUST FOR EXAMPLE PURPOSES* Computer : 125W Fan: 150W Lights (on 8 hours a day,...


8

For a multi-bulb fixture the LED units do not want to be in the area where high heat is generated as would be the case with incandescent or especially with halogen bulbs. CFLs have their own special considerations if they are used in situations with special types of lamp dimmers. Such special dimmers may not be compatible with LED lighting modules. ...


8

Most 3-way lighted switches work by adding a light between their line and load terminals: This actually causes a small current to flow through the load (light) -- with incandescent or fluorescent bulbs, it's not enough to actually cause the light to go on. But with your LED blub, it's enough to at least start the bulb. Your potential solutions: Replace ...


8

It's not the wiring. It's the LEDs themselves. LEDs have a characteristic delay when turning them on which may be more than you're used to from a lifetime of incandescent bulbs. Swap the LEDs from one position to another, and the problem should move with the bulb. Replace the LED with the equivalent incandescent (temporarily) and it should go away ...


8

This is splitting hairs... The concept of "grey energy" for powering of parasitic devices is severely overblown. You cannot just shut down a power generation plant, the plant ITSELF is a "parasitic load" on the grid if nobody is using that energy. So worrying about fractions of a watt, even spread across the entire planet, is an exercise in futility compared ...


7

Led lamp color is measured in kelvins. Warm White is 2700 kelvins or 27K. This is 'supposed' to be equal to incandescent table lamps. Next is 30k which supposed to be equal to halogen. Next is cool white which in LED's can range from 39k to 45k. The next is 50k and then 65k. The higher the number the bluer the white is. It sounds like you want 27k. ...


7

All lamps have a size designation which is stated in eights of an inch (1/8"). That particular lamp will most likely not fit in your fixture if it is designed to take a standard A-lamp. That is an R30 size lamp which is 3-3/4" wide. An R20 style lamp (2-1/2" wide) would be more in line size wise with an A-lamp, which is actually an A-19.


7

Yes, you're looking for lights with a high lumen output. Since LED/CFL bulbs don't convert heat to light, the wattage isn't directly proportional to the light output. As an extreme example, consider that a 2 watt laser is powerful enough to burn some materials, or blind you! What you'll likely find is that more expensive LED bulbs from lighting specialty ...


7

Simply put, you have the wrong type of switch for the bulbs you have installed. Most (not in every scenerio) LED bulbs require you to install an ELV type dimmer. What you have installed is a standard incandescent dimmer. There are three main types of dimming switches. Incandescent, CFL (for incandescents, fluorescents, and SOME LED bulbs), and ELV (for ...


7

Rundown in layman's terms: Light switch to outlet. You will see a lot of these in older homes. By code for a long time in a lot of areas you had to be able to turn on a light from a switch accessible when entering a room. Easiest and most cost-effective way to do this is put switch to outlet. I had six rooms in my house like this. Dimmer to outlet. For sure ...


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