LED Tube Light Vs Fluorescent Tube Light
Posted by
NaBa Green Energy
In this Article we will be comparing LED Tube Light and Fluorescent Tube Light by some characteristics. Such as
- Function
- Light Output
- Power Consumption
- Directivity
- Life Span
- Color Temperature & Color Rendering Index
- Color
Fluorescent Tube is a gas discharge lamp, that contains gases like Mercury. It produce short wave ultraviolet light that gets transformed into visible light, the inside of the tube has a phosphor lining. Then the 80% of electrical energy is converted into heat energy , 20 % only used for visible light. The energy produced converts into more heat than Led lights.
Light Emitting Diode is a semiconductor diode. It consist of p-n junction diode, when it is in forward biased the electron recombine with holes, then it release some energy in the form of photon( visible light). The electrical energy is converted into 80% light energy, remaining 20% being heat energy. LED does not contain mercury. No harmfull chemical (like mercury) are used.
Light Output:
T8 Fluorescent tube lights are available with different kind of rated light output and power consumption.
For example 36 watts fluorescent lamp, light output (Luminous Flux) is 2000 lumens, so system efficacy is 55 lm/ watt. Rated life is 5,000 hrs. Tube light efficiency comes down with time.
Lux at the ground = 9.18, Lux/watt =0.50
If using Aluminum Reflector, it can reduce 13% of output light. Now the light output is 1566 lumens
Lux at the ground =15.71, Lux/watt =0.43
If using prismatic Refractor, it can reduce 8% of output light. Now the light output is 1656 lumens
Lux at the ground =16.62, Lux/watt = 0.46
As we all know the efficiency is very high for LED Tube Light over the other lights. So the Luminous flux is consistent for rated life and power consumption also should be low.
Power consumption - 16 watts, System Efficacy -123 lumens/watt, So total light output( Luminous Flux) is 2000 lumens. It should be maintained for Rated life(50,000 hrs). Life span is very high for led lights over other lights. Lux at the ground =68.53, lux/watt =4.28
Reflector is not required for LED lights because of Directivity (Beam Angle).so the light output should not be wasted compare than Fluorescent lamp.
Power Consumption:
Normally the Fluorescent lights are available in 36 watt, but it runs using electronic ballast (called solid state ballast) which consume above 12 watts power.
Magnetic Ballast, the stating modes are Programmed stat, instant stat, and rapid start Lamp flicker index is 0.04-0.07; Dimming is not available for this ballast
Hybrid Ballast, the stating mode is rapid stat, Lamp flicker index is 0.04-0.07. Dimming is not available for this ballast.
Instant start Ballast supply a high initial voltage (over 400V for 4 ft Tube) to start the lamp. High voltage is required to initiate the Discharge between unheated electrodes.
Rapid Start Ballast supply 200-300V to start the lamp, which can heating the electrodes to approximately 1470˚F(800˚C). It starts the lamp with brief delay but without flashing. And for the Fluorescent lamp, warm up time is also minimum 5 minutes.
As we all known using LED Tube Light the power Consumption should be very low. And no need to use electronic ballast because it runs by constant current and voltage. We can’t see the flickering in the range of voltage 85-285VAC and Dimming also available for the led lights. LED driver are used in LED Lamp. So LED Tube Light has a potential benefits like quick start compared to Fluorescent Tube Lights.
Directivity:
Beam Angle is very important in every lighting technology. For Fluorescent lamp Beam angle is 360 degree. We can calculate the beam spread only for 270 degree, 90 degree beam angle is wasted
Beam Spread = 48.6 (Recommended pole height is 10 ft)
Led lights are available with variety of Beam Angle, Beam Angle is 120 degree for our Led Tube Light, we can calculate beam spread for 120 degree
Beam Spread = 21.6 (Recommended pole height is 10 ft)
The light output is not wasted in Led Tube Lights compare than Fluorescent Tube Light.
Color:
Fluorescent tube contains mercury gas, which can discharges and emits 65% of light in 254 nm and 10-20% of light in 185 nm. It will emit the yellowish white color. It has a low Color temperature and Color Rendering Index (Color Tempreature-4100 Kelvin, CRI-80)
Led light has a high correlated color temperature of 5500k -7500k. The sunlight has a color temperature of 6500k, so led light is equivalent to the sunlight. And CRI is also very high (above 90). It can emit the cool white color in the spectrum of 380-740 nm. For Humans also the visible spectrum is 380-740 nm.
Monday, September 20, 2010 | 0 Comments
LED Indoor Lighting
Posted by
NaBa Green Energy
Labels:
Home improvement lighting,
Hospital lighting,
Indoor Ceiling Lights,
Indoor Down Lights,
Office lighting,
Shop lighting
We have been discussing about outdoor lighting at length, LED has huge potential for Indoor lighting, which can be characterized by
- Efficiency
- Color temperature
- Rendering
- Color
- Dimming
- Directionality
Office lighting/Ambient lighting
Office lighting is the general purpose lighting in office . These may include recessed down light, surface mounted ceiling lights, LED Tube lights and table lamps.The LED office lighting not only used for reducing electricity consumption and also used for
- Improves productivity
- Increasing mental awareness
Mental Awareness:
The incandescent light affects human in two ways,
- Light enables us to see and feel things. Light regulates our body rhythms such as the sleep/wake cycle. Different types and levels of light can affect a person's ability to see clearly, identify people and objects, and drive safely.
- It can also increase sleep efficiency of older adults and reduce symptoms of seasonal affective disorder, felt by many people during winter months.
The LED lights will be very bright which helps us to see clearly. So it will be very helpful to human brain and increase the mental awareness. This light will reduce a sleeping efficiency and their laziness.
Productivity:
LED lights can reduce the irritation of the eyes, breakdown of vision, headaches, indigestion etc. These symptoms can be disabling while it certainly reduce worker productivity and spoiled their health. eyestrain will come from invisible light, flickering lamp and inadequate light. LED lights are energy efficient and it can reduce eyestrain which in turn leads to improved productivity.
Shop Lighting:
Shop lighting with efficient solid state lights using LED will results in better sales while saving money by reducing energy usage and maintenances cost
- Sales can be increased in shops by use different colors of led lights…it will increase the sensation of our mood.
- LEDs are available in red, orange, amber, yellow, green, blue and white.
- Different lighting condition can change the mood of people of shopping in building. Then LED colour lighting will lead to an improvement in mood , thinking capacity will be increased.
Hospital lighting:
Hospital or health care facilities can use ultra high efficiency led lights with replacement of CFL, HID etc..
The Led lights is not only safe and toxic free which means it does not have mercury toxic content…so it protect us from mercury emission…and this lighting easy on the eye also, LED lights will increase vitamin ‘D’ and decreasing dental decay
VITAMIN ‘D’:
- Some LEDs are promoted as producing ultra violet (uv) radiation .Its is shorter than the visible lights, in the range from 10nm to 400nm. UV range from 290 to 315nm , it can produce the synthesis of vitamin ‘D’. which is necessary for proper bone development and maintenance. Sufficient vitamin ‘D’ to have eliminated the incidence of bone -related problem.
Reducing dental decay:
- Lack of phosphorus and vitamin ‘D’ is the chief cause of ‘DENTAL DECAY’ or ‘DENTAL CARIES’. The phosphorus and vitamin ‘D’ are needed in order to prevent tooth decay. Phosphorus is needed in the saliva to enable this secretion to act as buffer solution , keeping enamel ,destroying acid from accumulating. So LED can easily reduce the problem of dental decay.
Wednesday, August 04, 2010 | 0 Comments
Light Spread in LED compared to Mercury vapor and High pressure sodium street lights
Posted by
NaBa Green Energy
Labels:
High Pressure Sodium street light,
LED Light fittings,
LED street light,
Mercury vapor street light
As discussed in my previous articles LED technology is growing leaps and bounds, we will compare the light throw of street lights. It has many advantages compared to other light technologies such as
- Even distribution of light from LED street light creates a better environment.
- Due to even distribution the visibility improves tremendously.
Mercury vapor street lights
Mercury vapor lamp is a gas discharge lamp that uses mercury in an excited state to produce light. For sake of comparison we will use a 60 watts mercury vapor street light, with following features
- Life span 16,000-24000 Hrs
- Power consumption -60 watts
- Required Beam angle-360, considering pole height of 10 feet,
In the above scenario, 90 degree beam angle is wasted. We can calculate for 270 degree beam spread only.
Mercury vapor lamp gives 30 lumens per watt, totally flux-1800 lumens
Lux = foot candle x 10.76(for 10 feet pole height 1fc=100 lumens) =(18 x 10.76) 193.68
Lux/watt = 3.2
High Pressure Sodium street lights
As we all know sodium vapor lamps cause little light pollution than mercury lamps. It is a high intensity discharge lamp that uses sodium high pressure as the primary light producing element. We will compare 60 watts high pressure sodium vapor street light with following specification
- Better Life span is 20,000-30,000 hrs compared than mercury lamps
- Power consumption -60 watts
- Required Beam angle -360,considering pole height of 10 feet
To calculate beam spread, Beam width = angle x. 018 x distance=64.8 feet rectangle
Based on the 270 degree beam spread as discussed above. 60 lumens per watts, totally flux=3600 lumens
Lux = foot candle x 10.76(for 10 feet pole height 1fc=100 lumens) =(36 x 10.76) 387.36
Lux/watt =6.4
LED street lights
Coming to led street light, We all know it can produce more light with less wattage. Below is the calculation. 60 watts led street light is used as replacement of 120 watts high pressure sodium vapor lamp. we will use same 60 watts led street light with following specification
- Excellent Life span is 60000 hrs
- Very low Power consumption -60 watts
- Beam angle -120 degree
Full beam spread is used in this scenario, because LED gives only light at 120 degrees.
Based on120 lumens per watts, totally flux-7200 lumens.
Lux = foot candle x 10.76(for 10 feet pole height 1fc=100 lumens)=(72 x 10.76) 774.14
Lux/watt = 12.90
Features | Mercury vapor lamp | High pressure sodium lamp | |
Power consumption | 60 watts | 60 watts | 60 watts |
System efficacy(lumens/watt) | 30 | 60 | 120 |
Flux(total lumens) | 1800 | 3600 | 7200 |
Lux | 193.68 | 387.36 | 774.14 |
Lux/watt | 3.2 | 6.4 | 12.09 |
Life span | 16000-24000 hrs | 20000-30000 hrs | 60000 hrs |
This calculation clearly shows led lamp lux value is twice than high pressure sodium lamp and four times than that of mercury vapor lamp. Mercury vapor lamp puts out bluish light , because it contain some amount of toxic mercury content. High-pressure sodium lamps produce light from the yellow, red and orange spectrums.The LED based efficient lighting puts out white light because consists of various colors, which undergo varying degrees of refraction and diffusion.
This led light used to avoid the hot spots and wasted light I mean beam spread of the light. Visit us at link to learn more about the LED street lights
Monday, May 10, 2010 | 0 Comments
Subscribe to:
Posts (Atom)
