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  2. LED lamp - Wikipedia

    en.wikipedia.org/wiki/LED_lamp

    Low power factors can result in surcharges for commercial energy users; CFL and LED lamps are available with driver circuits to provide any desired power factor, or site-wide power factor correction can be performed. EU standards requires a power factor better than 0.4 for lamp powers between 2 and 5 watts, better than 0.5 for lamp powers ...

  3. Haitz's law - Wikipedia

    en.wikipedia.org/wiki/Haitz's_law

    Besides the forecast of exponential development of cost per lumen and amount of light per package, the publication also forecast that the luminous efficacy of LED-based lighting could reach 200 lm/W (lumen per watt) in 2020, crossing 100 lm/W in 2010. This would be the case if enough industrial and government resources were spent for research ...

  4. Thermal management of high-power LEDs - Wikipedia

    en.wikipedia.org/wiki/Thermal_management_of_high...

    For heat transfer between LED sources over 15 Watt and LED coolers, it is recommended to use a high thermal conductive interface material (TIM) which will create a thermal resistance over the interface lower than 0.2 K/W. Currently, the most common solution is to use a phase-change material, which is applied in the form of a solid pad at room ...

  5. Power factor - Wikipedia

    en.wikipedia.org/wiki/Power_factor

    The presence of reactive power causes the real power to be less than the apparent power, and so, the electric load has a power factor of less than 1. A negative power factor (0 to −1) can result from returning active power to the source, such as in the case of a building fitted with solar panels when surplus power is fed back into the supply.

  6. Orders of magnitude (power) - Wikipedia

    en.wikipedia.org/wiki/Orders_of_magnitude_(power)

    1.1 × 10 3 W tech: power of a microwave oven: 1.366 × 10 3 W astro: power per square meter received from the Sun at the Earth's orbit: 1.5 × 10 3 W tech: legal limit of power output of an amateur radio station in the United States up to 2 × 10 3 W biomed: approximate short-time power output of sprinting professional cyclists and ...

  7. High-CRI LED lighting - Wikipedia

    en.wikipedia.org/wiki/High-CRI_LED_lighting

    Cool white fluorescent lamps have a CRI of 62, however fluorescent lamps containing rare-earth phosphors are available with CRI values of 80 and above. [ 2 ] For CCTs less than 5000 K, the reference illuminants used in the CRI calculation procedure are the spectral power distributions (SPDs) of blackbody radiators; for CCTs above 5000 K ...

  8. TI-59 / TI-58 - Wikipedia

    en.wikipedia.org/wiki/TI-59_/_TI-58

    Here is a sample program that computes the factorial of an integer number from 2 to 69. For 5!, if "5 A" is pressed, it gives the result, 120. Unlike the SR-52, the TI-58 and TI-59 do not have the factorial function built-in, but do support it through the software module which was delivered with the calculator.

  9. Wall-plug efficiency - Wikipedia

    en.wikipedia.org/wiki/Wall-plug_efficiency

    The latter is commonly measured in W⋅nm −1. Φ e,λ [nb 4] watt per metre W/m M⋅L⋅T −3: Radiant intensity: I e,Ω [nb 5] watt per steradian: W/sr: M⋅L 2 ⋅T −3: Radiant flux emitted, reflected, transmitted or received, per unit solid angle. This is a directional quantity. Spectral intensity: I e,Ω,ν [nb 3] watt per steradian ...