| 摘要 |
A device 2 for controlling public space lighting comprises means 12, 12, 22 for providing a first (decreased) voltage or a second (increased) voltage to a public space light 18 and a transmitter and a receiver 26 to communicate with other devices; the device 2 supplies the second (increased) voltage to the light 18 when the presence of a person or vehicle is detected by a sensor 28 of the device 2; or when another similar device indicates that such a presence has been detected via the transmitter and receiver 26. When the presence of a person or vehicle is not detected for a pre-set period of time, the first (decreased) voltage is supplied to the light 18. The detector is preferably an infra-red motion sensor and the decreased voltage is preferably supplied by the output of autotransformer whose input is supplied by the increased voltage. |
