Quote:
Originally Posted by adc
Not sure why you'd say that.
The hotter the bulb in free air, the hotter it will also be inside a sealed headlamp. 
While EAS's test won't tell the true temperature inside the headlamp, it's stil relevant as to which light source will contribute more heat. It's not like the bulb will magically be cooler inside the headlight assembly... |
100% correct. A LightSource that emits more heat will result in a higher temperature within a sealed headlamp.
Quote:
Originally Posted by mds82
Well then - that would be a real life example then...........
If you dont want t real life example, then at least let the lights stay on for 30 minutes or more. put them inside a closed box that doesnt have any air movement... at least that will be closer...
the point that is most misleading with your tests - LED's do create very little heat compared to halogen or Xenon bulbs, however, the way the heat is dealt with is VERY Different. TIME is the crucial factor for these tests..
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Except the fact your "closed box" test does not take engine heat into account. On a headlamp - cooling is only at a minimal level (only from ambient temperature and wind resistance on the headlamp lens). Time would only affect this in a negative manner, with summer heat making the matter even worse.
The heatsink used in both the AiB and even LUX (both material and size/design) will allow heat to dissipate (aluminum has excellent thermal conductivity) from the LED, keeping it within safe operating temperature. The same concept can be compared with a computer processor/fan assembly. A quick explanation can be found here:
http://www.frostytech.com/articleview.cfm?articleID=233.
Heat is a serious issue. Even more so with Light Sources emitting heat at higher temperatures than OEM.
LightSource Temperatures (in order from lowest to highest temperatures):
1. LED
2. OEM Halogen or Incandescent Bulbs
3. Tinted "Xenon" type Halogen bulbs
4. HID
HIDs were never disputed as not being the brightest, but there is no free lunch. This generally comes at a cost with higher heat and equal uneven light distribution as OEM.
A similar issue with heat happened on the AiB DriverPacks last year during the summer months, which have since been upgraded (at no additional cost) to handle these types of environments. LUX only had this happen a short while ago, requiring mounting of the DriverPacks externally of the headlamp.
However, a Halogen or HID element is a higher source of heat that will keep the environment (keep in mind less than a cubic foot) within the headlamp at a higher temperature than an LED. Even tinted halogen bulbs (ie: GP Thunders) will run hotter than the OEM bulbs as well as suffer from lumen output due to higher kelvin temps.