| 摘要 |
<p>A ballast for regulating current through at least one gaseous discharge lamp responsive to thermal conditions around the ballast. A capacity circuit including a power capacitance is utilized to provide at least a part of the current regulation. The capacity circuit is responsive to a change in temperature and is capable of switching either abruptly or gradually from one capacitance level to another capacitance level. The impedance of the capacity circuit is therefore increased as the temperature increases thereby limiting current through the at least one gaseous discharge lamp during a high temperature situation. Furthermore, this decrease in current has little, if any, overall effect on the light output of the lamp.</p> |
