Effect of sodium/mercury ratio and amalgam temperature on the efficacy of 400 W high-pressure sodium lamps
- 1 June 1974
- journal article
- research article
- Published by SAGE Publications in Lighting Research & Technology
- Vol. 6 (2) , 62-68
- https://doi.org/10.1177/096032717400600202
Abstract
400 W high-pressure sodium arc tubes containing different quantities of mercury in the sodium/mercury amalgam were placed with one end submerged in a bath of molten indium which controlled the temperature of the amalgam. For a series of different amalgam temperatures the following parameters were measured on 240 V supply: voltage, current, power input, self-reversal width and luminous flux. Information taken from these graphs and replotted as a function of the amalgam composition provided the amalgam temperature and amalgam composition for maximum efficacy at 400 W. A broad maximum was observed with a peak of 116:t 1 tm W- 1 at an amalgam temperature of -640°C with a mole fraction of sodium of 0. 7. Now these optimum conditions have been established, higher efficacies still have been obtained using superior arc tube materials.Keywords
This publication has 1 reference indexed in Scilit:
- Luminous Efficiency of the High-Pressure Sodium LampJournal of Applied Physics, 1971