| 摘要 |
An electrical socket 1 has a sensor arrangement to detect whether pins of a plug have been inserted, comprising a radiation emitter 60a, 61a and a detector 60b, 61b for each of at least two pin-receiving spaces 5a, 5b. A line of sight connecting the emitter and the detector passes through the pin receiving space such that insertion of a pin alters the radiation level received by the respective detector. The socket further comprises a signal processor (150, Fig 15) arranged to receive signals from the detectors and determine that a power supply is to be connected to electrical terminals to contact with the pins if the at least two pins are determined as having been inserted into the pin receiving spaces. The radiation may be infra-red. A shutter requiring the simultaneous insertion of two pins is also described. |
