LED vs Incandescent vs CFL & Fixture Wattage Limits

The reason for a stop point to be labelled 60W and rising is heat dissipation from the lamp and the propensity for it to cook the fitting, any shade and the incoming cables. So for a 60W-rated fitting it doesn't matter what the light source is so long as the dissipation doesn't exceed 60W. The notice is put on there because there are surviving heritage lamps capable of being inserted into said fittings that can dissipate rather more then this, and the manufacturer and retailer want to cover their backsides commercially in the event of the user selecting one of these inadvertently for use with it.

Feel free to go up in lumens by substituting lamp types, though be aware that 60W of LED is not available to fit conventional light fittings, and would be dazzlingly bright if it were!

Good Answer. It is about the heat issue. I'm actually surprised that the marketing people have not addressed this on the packaging. While they have addressed the equivalent light output (incandescent verses their product) they seem to have failed to address the equivalent heat dissipation issue.

Since the efficacy improvement is nearly 4:1 it might be possible to jump to a conclusion that the heat dissipation follows the same ratio. But, it is a lot more complicated than that. In fact, the orientation of a CFL makes a lot of difference in how long it will last. And while that is true, it is difficult to find information about that, especially on the packaging.

Very few people know or understand the physical characteristics of the products sold in the market. And many of the sales folks.....barely know how to find their way home so you can't really get good information there either. Just remember, there is no such thing as a foolish question. That dosen't mean, however, that there isn't some pompous jerk ready to pick on you for asking.

I must disagree with this statement, "Just remember, there is no such thing as a foolish question."

We see many very good examples of foolish questions here on CR4 every day. And foolish doesn't describe some of those questions adequately.

Current question is not foolish at all.

(pompous jerk)

I've gone up to 100 watt equivalent lumens in the reg base fluorescent, with no problems...

I'd have to agree with you except that I think you are using different standards. Perhaps you are referring to those kinds of questions that fall into the classification of silly to dangerous questions, not to forget those which seem to make no sense. The latter being a mixture of incomplete discriptions, incomplete sentances, and incomplete thoughts.

And I do wonder why some people go to the trouble when they have no clue. For those, I say, "Open Season"!

Dazzlingly bright, but such a narrow color band that you cannot use it to see by. -- JHF

watts are a measurement of heat, not light output, a fair amount of testing goes into any "label prior to that label being applied to a product used by the public. get all the lumens you can regardless of type of bulb you buy.

why is it when a label clearly states a maximum that people always want to exceed it or look for a way to defeat it?

Watts are electrical power, not heat. Heat is the result of system inefficiencies, or resistance in a heater.

Some of that power (in Watts) is converted to light. Magnetic ballasts will generate the most heat. In an unvented light fixture, a magnetic ballast might be a problem when you ramp up the number of lumens you wish to achieve. Maybe that is why they all switched to electronic ballast!!!

My point is simply this. Sometimes new products hit the market before all the testing has been done. That makes it "Buyer Beware".

Anybody know a recipe I can use for all of these tomatoes? I don't like ketchup.

One of my favorites, American Goulash.....

http://www.food.com/recipe/american-goulash-388153

Spaghetti sauce. Always spaghetti sauce. Best thing the Italians ever invented...next to Sophia Loren. Who I wouldn't mind being next to but isn't this getting off-topic?

Topic: Whatever the terminology, whatever causes the heat, the reference is solely to incandescents because they produce a lot of heat. And you don't want to burn anything up.

W = E x I or voltage x current. Since voltage is constant, the current is the determinant. But wait, I = E/R or voltage over resistance, so really the Wattage is based on the resistance of the load or I^2 R.

Each type of bulb produces a different amount of heat, which is based on the efficiency of changing electricity into light energy. As we know, tungsten bulbs are not very efficient compared to CFL's and LED's, so they put out less light and more heat. I haven't seen any CFL's close to 60 watts with a standard socket (the most I've seen is 23W). I would think that a 60 W CFL would put out a tremendous amount of light. Ditto for a 60 W LED.

Most of your lighting manufacturers have pretty good tech info. If I remember correctly the lumens output comparisons are roughly like so: 1watt of incandescent light = 1 lumen 1watt of florescent light = 4 lumens 1 watt of LED light = 3 lumens

Here's a lumens per watt comparison chart.....↑

Here's a lighting types comparison...↓

http://ext.homedepot.com/shopping-tools/light-bulbs/bulbcomparison.html

If you have a massive collection of small 60 watt halide 'energy saving' downlights in your home and a electricity meter that drains your credit card with the power for the lights and the air con to cool things down, plus you have the 'continuous' pain of getting in a tall ladder to change the downlights when they burn out, then surely it is time to consider the available options, like LEDS.

I discount the CFL's because of the mercury and the long term environmental disposal issues.

If you are an investigating engineer, and you have the halide downlight issue, then buy some LED samples and compare.

Things to consider:
1. LED lamps will last usually 5-10 times longer
(around 50,000 hrs or if ON for 10 hours per day, around 12 years).
2. LED colours usually come in warm white, natural & cool (blue) white - your choice.
Try 4 watt or 6 watt LEDS, (of appropriate output colour), and compare light.
3.The LED beam angles can also vary. Try more sample to test the beam spread.

Bottom line benefits:
1. This is a 90% electricity saving for the lighting.
2. Those with say 24 halide downlights can also turn off the 2HP air conditioner.
3. The tall ladder can stay in the garage.
4. Import LED lights from China. Sell replacement lamps to friends and make a profit.

Here is a link for those of us who aren't engineers to help us to understand electrical terms: www.ia470.com/primer/electric.htm .

They explain as follows:

Electricity is the flow of electrons from one place to another.

Electrons flow through some materials more easily than others - the amount of ease or difficulty with which they flow through the material is called Resistance and is measured in Ohms.

The flow of these electrons is called Current - (Now I find this confusing. I think they mean the rate of flow, because that is their definition of electricity?) - and is measured in Amps.

Making electrons flow through a material requires an attractive force to pull them. This is the Electro-motive Force, the amount of which is measured in Volts.

The amount of work performed in this process is called power and is measured in Watts.

Ohm's law states that one Watt is equal to the work performed by one Amp pushed (I would say "pulled", but I'm only a designer and not an engineer) by one Volt through a resistance.

Through 1 ohm of resistance, not any amount of resistance. Ohms measures the resistance to current flow. Mhos measure the ease at which current flows, it is the opposite of ohms. -- JHF

Thanks!

So is current, measured in Amps, the amount/number of electrons pulled through the resistant material or the rate/speed at which a fixed amount or number of electrons are pulled through??? This is what I find a bit confusing!

Current is measured in Amps or Amperes. An Amp is defined as 6.24 x 10^18 electrons/sec flow. Also, an Amp can be defined as one Coulomb/sec.

The speed the electrons travel is dependent on the material. Electrons travel at the speed of light, however the material slows the electrons down. In copper, they travel at about -3% slower than the speed of light, while other materials slow down the electrons even more.

The speed of the electrons is not related to the current flow - think of current flow as volume of electrons moving past a point or cross section. The work is done by the number of electrons, not the speed of them. That's why an Amp is defined as # electrons flowing in a given amount of time. The work is done by the electrons and is defined as power (Watts).

It's like water coming out of a hose, in a sense. (I deal better with mechanical mental models)

So current is the amount of electrons passing through the material and not the speed with which they pass through, right? Thanks for all the great responses!

Water equivalents to help explain.

Voltage is pressure - like the height of water in a tank (V) (volts)
Resistance - the (reverse) diameter of the pipe (R) (ohms)
Current - volume of water flow in a certain time
(depends on pipe diam & tank height) (I) (amps)

So Voltage (V) = Resistance (R) x Current (I)
Power (watts) = voltage (V) x current (I)

In simple terms, a 2200 watt electric kettle plugged into a 220 volt socket
draws a current flow of 10 amps, when turned on.
If you look at the molding on a wall socket, it should say max 10 amps.
That is, the socket is designed to allow a current flow of 10 amps safely.

Going further with the same kettle example, if it works on 220 volts and it has a 10amp current flow,
then the resistance of the heating coil is 220 = R x 10 or the heating coil has a resistance of 22 ohms.

Some countries have higher wall socket voltages, 240V, 220v vs 110v etc.

To deliver the same power (watts), then the current has to be higher
if the voltage is lower, so the wires have to be thicker .. or they also will get hotter.

I hope that helps a bit.

Thank you for another great explanation :). I wish that more time was spent on technical subjects like this when I was in college! I tend to think in a linear fashion and when presented with a lot of information on lighting without more background in the basics of electricity, it is very difficult to remember much of it. I love to learn and I find CR4 to be a terrific resource!

I understand your comments about college and the often lack of simple explanations.
It is like transistors and the water model again, and comparison to a tap.
They have an inlet (EMITTER),
outlet (COLLECTOR)
and control handle (BASE).

When a transistor acts as a switch, (including memory),
the control handle is below a threshold, so the water output flow is off.
Similarly when the control handle is turned on, water output flow is on.

Transistors can also be an amplifier ...
imagine that a tap that is running
and there is a little increase change on the control handle
(in the transistor that is a small variation of voltage between the BASE & EMITTER),
and this causes a big increase in the water flow.
Similarly, while the tap is running and there is a little decrease on the control handle
then there is a substantial decrease in the water flow.

So there you have it, a transistor can be a switch or an amplifier.

This is a common misconception and is put up for ease of demonstration...

People like the analogy to water flowing in pipes, but it really isn't a good demonstration for accuracy's sake. Water molecules in a hose travel faster than electrons in a 15kV line...in the point A to point B sense.

Electron "movement" in copper, for example, is actually only about three inches per hour. This is nowhere near the speed of light...let alone "-3% slower" (which is actually faster than light with the use of a double negative...I think you meant 3% slower).

Electron "flow" is the movement of an excited field of potential energy which does indeed move much faster then 3 inches per hour...but not quite light speed.

That's the way I'd always understood it, but, since I have no formal training, I was not going to say anything. Thanks for verifying me 50+ year ago casual reading. (Not that it was a while back, but it was a radio electronics course about vacuum tubes in radios a friend of my dad's gave me that got him into electronics right after WWII. At the end of the course it mentioned that there are these new thingies call transistors that some people said may someday reduce the need for vacuum tubes!) -- JHF

The water flow analogies link the 'common and seen' with the 'harder to comprehend' world of electron agitation at an atom level. The speed of flow is a red herring. Accuracy related to transmission speed is not at the heart of the demonstration, the 'ah ha' factor related to realisation of how things work is paramount.

Pete, I agree with your answer from a physics point of view, but your answer doesn't help the poster with his question and I think confuses the issue. You're speaking of drift velocity, which I agree is very slow. This was not the question asked. The question dealt with current and how the speed of electricity affects current. If you answered him with the drift velocity, you would definitely confuse him. So technically, I should have answered the wave travels at near the speed of light and even though it is correct, I think it would've left many here confused.

I think this is the difference between practical information and being too precise. Just my observation.

If it is any help, I just saw an ad for a lamp stand that specified the use of either a 150W incandescent or a 42W CFL.

Friend,

The 60-watt is because of heat (96-99% of incandescent electricity is lost as heat). It is a code and legal requirement. If the fixture is well ventilated or can hold the bulb size, you certainly can go up in lumen output with a CFL or LED. CFL's are available up to 200w equivalent and LED's to at least 100w equivalent.

Cut-off point??? Weight, size, cost, maximum size available, ventilation.

--JMM

Dear Mr.scotchdrnkr,

I feel it is very simple.

Each type of Lamp has a definite efficiency, in converting the Electrical Energy to light energy. The INCANDESCENT BULB has the LEAST EFFICIENCY - to the extent of max. of 5% only, that too with COILED COIL type bulb, balance goes as Heat Energy dissipated to the surrounding.

You have to decide the ILLLUMINATION LEVEL required based on the Efficiency and cost aspect, it can be decided. My experience - cheap CFL lamp does not last long for a month - for the average use of 5 hours, standard or branded CFL light worked for 3 years for the same average 5 hours of use.

DHAYANANDHAN.S