LED Lamp: Sites Black List. Blocked Payload Type: HTML
LED Lamp: Sites Black List. Blocked Payload Type: HTML
LED Lamp: Sites Black List. Blocked Payload Type: HTML
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GFI WebMonitor 4
Access for 10. 123.20. 4 was denied by GFI WebMonitor for ISA Server. Details: Sites black list. Blocked payload type : Html
LED lamp
LED lamps (light-emitting-diode lamps) sometimes also called solid state lamps or LED lightbulbs are becoming very popular in last years. They are the economical source of light. Although their ligth flux is usually (in 2010) not equal to the incandescent bulbs or energy saving fluorescent bulbs, their advantage is very low power consumption, in most cases 0.5 - 3W. Fortunately, the power and light output of new LEDs is rapidly rising every year because they are undergoing rapid technical develompent. We can choose different colors, but probably reach for white LEDs. The white LEDs have choice between different light temperatures, from warm white imitating conventional bulbs to daylight (2700 - 10 000K). You also need to decide between point and diffuser LEDs. These choices are many types of radiation from the angle 10 to 150 . Price LEDs with technical progress continues to decline, the luminous efficiency grows. Conversion of intensity to the light flux can in my online calculator . To power the LED bulb from the mains it is needed to create a suitable power supply or ballast. For low power and small sizes the transformer is not a good choice, therefore, is most commonly used precipitation capacity using a capacitor to AC 250V ~ best in class X 2. Resistance in series (220R 2K2) is used to limit inrush current. The capacitor is provided by a parallel security resistor around the 1M resistor, which ensure its discharge after switching off. The reduced voltage is rectified by a small diode bridge. Most of the LEDs are designed for the current 20mA, this current corresponds (in case o small number of LEDs) to around 330nF capacitor. LEDs can be connected to series of different quantity, without changing the values of components to about 20. For larger quantities of LEDs and select a larger capacity. Online calculation of the components of LED bulbs can be found below. The most common size of LED is 5mm . For my first LED bulb i chosen 5 pieces of cold white LED 5mm with current of 20mA and a large angle of 150 . I built it into the E27 base of the old compact fluorescent tube. These diodes have luminance only 200mcd due to the large angle . For the second LED bulb I opted 15pcs of 5 mm LED with a typical brightness of 15,000 mcd and an angle of 25-30 . Its maximum current is 30mA, 3.1 V drop, lifetime 100 000h. The socket is again from the E27 energy saver. Source is improved with the electrolyte. This eliminates stroboscopic effect, and also protects the LEDs from inrush currents and spikes on the mains. LEDs are provided with current of about 20mA. Light is pretty decent. Warning! The power supply of this LED buld does not mean the galvanical isolation. The entire circuit including the LEDs is connected to line voltage . The conductive parts must be protected agains touch.
http://danyk.wz.cz/ledzar_en.html
3/22/2012 10:15:15 AM
LED lamp
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http://danyk.wz.cz/ledzar_en.html
3/22/2012 10:15:15 AM
LED lamp
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LEDs in a cap
http://danyk.wz.cz/ledzar_en.html
3/22/2012 10:15:15 AM
LED lamp
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About to close
And it shines ! :)
http://danyk.wz.cz/ledzar_en.html
3/22/2012 10:15:15 AM
LED lamp
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http://danyk.wz.cz/ledzar_en.html
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LED lamp
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http://danyk.wz.cz/ledzar_en.html
3/22/2012 10:15:15 AM
LED lamp
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http://danyk.wz.cz/ledzar_en.html
3/22/2012 10:15:15 AM
LED lamp
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About to close
http://danyk.wz.cz/ledzar_en.html
3/22/2012 10:15:15 AM
LED lamp
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in a light
It shines nice
http://danyk.wz.cz/ledzar_en.html
3/22/2012 10:15:15 AM
LED lamp
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Mains voltage : Mains frequency: LED voltage drop: Desired LED current: Number of series LEDs: Capacity of C1: Capacity of C2: Voltage on C2 (has to be rated to more than this): Resistors R1 and R2 (both the same):
Calculate
230 50
V~ Hz V mA
0 0 0 0 Reset
uF uF V ohm
Mains voltage : Mains frequency: LED voltage drop: Number of series LEDs: Capacitr of C1: Resistor R1: Resistor R2: Current through LEDs:
Calculate
230 50
V~ Hz V uF ohm ohm
0 Reset
mA
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