| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent wasteful consumption of electric power by lighting corresponding to a use state of the of room. SOLUTION: Two switching parts SW1, SW2 are installed at a device controlling the lighting of light source groups 1. The light source groups 1 are divided into the first group to which light sources 1a belong, and the second group to which light sources 1b belong. The first switching part SW1 can be operated freely and power source is supplied only to the first group and each light sources 1a are lighted when the switching part SW1 is turned off. The switching part SW2 operates when than operation is carried out, using an equivalent object indicating to have the priority. When the switching part SW2 is turned off, electric power is supplied to the first and the second groups and whole light source 1a, 1b of the light source group 1 are lighted.</p> |
