Re: Halogen Bulbs mr16

[Marc F Hult <MFHult@xxxxxxxxxxxxxxxxxxxxx>]

On Wed, 23 Nov 2005 16:05:08 GMT, "Jeff Volp" <JeffVolp@xxxxxxx> wrote in
message  <Uq0hf.154436$zb5.99213@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>:

>"Marc F Hult" <MFHult@xxxxxxxxxxxxxxxxxxxxx> wrote in message
>news:m9t1o1lkn8pn2951s73g3ovsp6grl2omiu@xxxxxxxxxx
>> On Sun, 20 Nov 2005 14:53:08 GMT, "Jeff Volp" <JeffVolp@xxxxxxx> wrote in
>> message  <o50gf.135184$zb5.33411@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>:
>>
>> >
>> >A cover or lens would keep dust from getting into the reflector in dusty
>> >location, and make it easy to clean.
>>
>> Well that too;-)  But ore importantly, UL now _requires_ that the 'quartz'
>> envelope containing the filament be covered with protective, UV-absorbing
>> glass in order for open-lamp luminaries to receive UL listing.
>
>Good info Marc,
>
>But I thought the fire hazard was from those big multi-hundred watt quartz
>floor lamps where drapes could fall on the hot bulb. I remember the problem
>several ago, and the related recalls and retrofits.  I didn't think it was
>an issue for the 20 to 75 watt ceiling spot fixtures.  There were already UL
>regulations in place to keep combustables away from such fixtures.
>
>Jeff
>

Right. 500 watt lamps previously used in torchieres no longer meet UL/US code.
The max allowed in now 300 watts.

An important mechanism in halogen lamps is the maintenance of the
envelope/capsule at a high temperature in order to reduce condensation of
tungsten on the walls and allow regeneneration of the filament through what is
dubbed the "halogen cycle". So the capsule of even small halogen lamps may be
very hot by design. Also the cover glass protects against glass shards should
the capsule shatter.

Marc
Marc_F_Hult
www.ECOntrol.org