"John Larkin"


Various references say that incensescent lifetime goes as voltage to
the -13 to
-16 power.


** The formula that predicts lamp life is only valid for a small range
around the nominal voltage, about 10%. The simplifying assumptions it is
based on are true only in this range.

Reducing the voltage by large percentages extends lamp life by factor of 10
or possibly up to 100 - the halogen cycle has SFA to do with it.


.... Phil