1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Sharp Introduces Nine New LED Lamps for Home Use

Discussion in 'Environmental Discussion' started by ken1784, Jun 11, 2009.

Page 3 of 3
  1. ken1784

    ken1784 SuperMID designer

    Joined:
    Dec 18, 2003
    2,940
    1,365
    67
    Location:
    Yokohama, JAPAN
    Vehicle:
    2010 Prius
    Model:
    N/A
    Yes, I like it.
    Regrading to light angle, please refer to following chart derived from Toshiba E-CORE LED information (Japanese only).
    [​IMG]
    black line: standard tungsten lamp
    red line: tungsten color LED
    blue line: white LED

    It is equivalent to tungsten lamps.
    Yes, the initial cost is high, but I can save a lot of electric bills and the replacement cost because of the long life.
    [​IMG]
    For 40,000 hours LED lamp life, I could save...
    vs tungsten: 28,000 JPyen electric bill plus more than 40 tungsten lamps (1,000 hours life) replacement cost
    vs CFL: 3,400 JPyen electril bill plus more than 6 CFL (6,000 hours life) replacement cost
    I think you are correct about Vf vs brightness.
    However, the LED lamp heat sink (the gray part is made of aluminum) becomes warm, so it has self warming-up function. :)

    Ken@Japan
     
    #41 ken1784, Jan 10, 2010
  2. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,074
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    I don't know what sort of commercial units there are. The ones I work with are custom designed.

    The cost is low, and they are very small. Mostly all it takes is a power MOSFET transistor and some sort of PWM driver. Many of these are available integrated into one IC, or you can use a small microcontroller and an external transistor. Depending on the particulars, you may need some sort of inductor to suppress RF interference.

    Tom
     
    #42 qbee42, Jan 10, 2010
  3. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,074
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    No cold start issues with LEDs - they start instantly, and at full brightness. LEDs are pretty happy to work at any temperature, as long as they don't over heat. All semiconductors fail quickly if they are allowed to over heat.

    Tom
     
    #43 qbee42, Jan 10, 2010
  4. icarus

    icarus Senior Member

    Joined:
    Apr 12, 2007
    4,884
    976
    0
    Location:
    earth
    Vehicle:
    2007 Prius
    Model:
    N/A
    Just bought a Feit, candle shaped , standard base 24 LED bulb, frosted globe, warm white color, under $10, Very nice light, burning just 1 watt according to the Kill-a-watt. I can't wait to try the Feit conventional bulb shaped bulb! As I said earlier, installing these in our off grid house will reduce our lighting load from ~.5kwh/day to ~.05kwh/day. I will have to leave 5 of them burning just to keep the inverter from going to sleep.

    One more interesting question is do the induce noise into AM radio like CFL ballasts do?
     
    #44 icarus, Jan 12, 2010
  5. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,074
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    No, not normally. If they use a PWM dimmer or a buck/boost converter they may produce RF interference. There isn't one simple answer because there are many ways to drive LEDs.

    Tom
     
    #45 qbee42, Jan 12, 2010
  6. icarus

    icarus Senior Member

    Joined:
    Apr 12, 2007
    4,884
    976
    0
    Location:
    earth
    Vehicle:
    2007 Prius
    Model:
    N/A
    As I said before, when we get below $10 and lumens rival ~60 watt bulb it will become a game changer,

    Thanks for the info Tom
     
    #46 icarus, Jan 12, 2010
  7. icarus

    icarus Senior Member

    Joined:
    Apr 12, 2007
    4,884
    976
    0
    Location:
    earth
    Vehicle:
    2007 Prius
    Model:
    N/A
    24 hours on the kill-a-watt and it read, .02 kwh, or 20 watts for an hour!

    Compare that to a 10 watt cfl for the same time would be .24 kwh for about the same amount of light! Getting there! Give me a few more lumens and I'll be a happy camper.
     
    #47 icarus, Jan 13, 2010
(You must log in or sign up to post here.)
Page 3 of 3