I wonder what the mtbf is for the led's vs the control electronics? As mentioned before it is strange that the new bulbs are made to look like the old - what about a new socket for the led's that will fit in a base housing the electronics - then we could get away from the standard antiquated screw in base... I have started to replace them although EDN's chart had a 90% manufacturing cost drop from now until 2015 - the old early adopter costs to get it going, or wait and hope others drive the industry and thus the costs down.....
There is one aspect of LED lamps that uniquely sets them apart - No RF interference. For a long time now, RF interference (particularly in the VHF / UHF range) from fluorescent lamps is well known. LED for the first time offers a clean source without this interference. It is major plus for many outdoor public areas. In addition, it would be a major plus even for business offices where public safety personnel are needed (such as EMS, Fire etc).
The "fixture" (such as the lamp base) could have the power conversion circuit (from wall 120/240VAC) and the "bulb" could be primarily the LED's + diffuser. The packaging often wouldn't be as tight physically and there could be one power conversion circuit for several "bulbs". The LED bulbs could be replaced or potentially the lamp base's electronic module could be modular and replaceable. I don't see why the power circuit would be very expensive, especially given the possibility of much more packaging freedom.
We should get a teardown of the driver and PFC or whatever else they use to understand this aspect better.
You are correct the added feature about the LED light bulb. As we know the Triac dimming and PFC features. The PFC is 100 % for the incandescent light bulb but when you use the Triac to dim the light, it burns the power away. LED light bulb doesn't and i can maintain PFC to reduce the E-cap which the conventional light bulbs needed.
The bottom line is improvement with the LED light bulb.
1. get rid of the E-cap and have high PFC.
2. While dimming, it saves the power,not burns away the power like the conventional light bulb.
3. there are quite a lot of protections of the circuits which doesn't exist in the conventional light bulbs. The extra protections are hidden in the LED drivers like the in-rush current limit, soft start, short circuit protection(over current), and over temperature protection..etc.
4. for the extra cost, you can have the color temperature control light bulb, to have the red LEDs to adjust the color temperature.
5. The new HV-LEDs give you higher efficacy and Lumens with less current.
"Does anyone know the temperature of the circuitry in a GU10 or A19/E27 LED bulb?"
I don't know the internal temperature but the hottest "60W" A-19 I've used is the Philips. The external heat sink temperature is about 122 deg F with a 73 deg ambient.
Though the life of electrolytics at the elevated temperatures in an LED are a concern, my greater concern are the life of the electrolytics in a SmartMeter. Last summer, 105-110 deg ambient temps were the norm here in Texas. The meters are "designed for 20+ year life." (Landis-Gyr spec sheet.) That's 175,200 hours in temps ranging from 15-110 deg F 24/7/365 x 20.
There have been cases where electronic capacitors in the small MR16/GU5.3 LED bulbs have failed after prolonged use where there was an increase in heat due to the use of electronic transformers and poor convection cooling.
My reading shows that the life time of various capacitors at 45°C ranges from 32,000 hours to greater than 15 years for long life ones, e.g., NAZV series. However, at 85°C the general purpose capacitor, e.g., NACE series is rated at 2,000 hours and the long life 40,000 hours, and others in the range of 6,000 to 32,000 hours, less than the life of the LED. We have measured heat sink surface temperatures of up to 72°C using compatible electronic transformers so capacitor life is probably a significant issue with heat being the real killer for caps.
I have seen no studies as yet comparing the performance of MR16 with constant voltage driver vs. GU10 with integrated driver, which would be interesting. My theory is the GU10 LED form factor will have a shorter life span than the MR16/GU5.3 due to greater componentry and additional heat, supporting the use of independent constant voltage drivers.
Does anyone know the temperature of the circuitry in a GU10 or A19/E27 LED bulb? don@ www.liteonled.com
Blog That A-Ha Moment Larry Desjardin 10 comments Have you ever had an a-ha moment? Sure, you have. The Merriam-Webster dictionary defines it as "a moment of sudden realization, inspiration, insight, recognition, or ...