Lamp rerating

The properties of a filament lamp can be approximated by power law function of voltage. When the lamp is used at a voltage other than its specified rating, then the following lamp rerating equations can be used to estimate the new operating point. The exact value of the exponent parameters will typically vary slightly with the particular lamp design.

:"V"_a = Applied voltage:"V"_d = Design voltage

*Rerated current = ("V"_a/"V"_d)^0.55 × current at design voltage cite web | title=Miniature halogen lamps; lamp electrical characteristics| author=Welch Allyn | year=2007| url=http://www.light-catcher.com.cn/PDF/en_literature/6.pdf | accessdate=2007-12-31]

*Rerated luminous intensity = ("V"_a/"V"_d)^{3.4 to 3.5} × Luminous intensity at design voltage cite book | author = Donald G. Fink and H. Wayne Beaty | title = Standard Handbook for Electrical Engineers, Eleventh Edition|publisher=McGraw-Hill |location=New York |year=1978 |isbn=0-07020974-X |pages=pp. 22–8 ]

*Rerated life = ("V"_a/"V"_d)^{-12 to -16} × Life at design voltage

*Rerated electrical power = ("V"_a/"V"_d)^1.6 × Electrical power at design voltage

*Rerated color temperature = ("V"_a/"V"_d)^0.42 × Color temperature at design voltage

References

* [http://www.light-catcher.com.cn/PDF/en_literature/6.pdf Lamp rerating equations]