On 12/11/2012 01:19 PM, Sjouke Burry wrote:
"john wrote in
:

Have a 10Watt, 12Volt Hologen lamp for a christmas decoration. But
the mains tranformer I have is only 6 Volts.

Apart from being a bit dimmer, would there be any other consequences
running at the lower voltage? Thanks.



Halogen has a build in cycle to keep the filament healthy.
That does not work at a lower temperature.
So running it at the wrong voltage will cause it to fail
early.
Other then that, for a decoration a dim bulb is no problem,

Nope. The halogen cycle is to keep the envelope clean. The high gas
pressure extends the filament life, by causing tungsten to be
selectively redeposited back on the same hotspots it came from.
Otherwise the tungsten redeposits randomly, and there's nothing to keep
the hotspots from necking down and failing just as early as in a
low-pressure bulb.

(We keep coming back to this every few months lately.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net