| 摘要 |
PURPOSE:To prevent accidents by a method wherein an enclosed switchboard is provided with a temperature detecting device, operating a switch by use of a heat sensitive element whose configuration is changed when the temperature of bus bars rises to a predetermined temperature and is returned to an initial configuration when the temperature falls below the predetermined temperature. CONSTITUTION:Breakers 2 are received in the unit chamber 1a of an enclosed box 1 while bus bars 3 and conductors 4a, 4b, which are connected to the power source side terminals and load terminals of the breakers 2 respectively, are received in a bus bar chamber 1b. A temperature detecting device 6 is attached to the bus bar 3. A bimetal, a shape memory alloy or the like is utilized for the temperature detecting device 6 and the configuration thereof is changed when a temperature is risen to cut an electric contact OFF while the configuration is returned to the initial configuration thereof when the temperature is reduced. According to this method, the temperature rise of the bus bars 3 is detected directly and alarm is outputted whereby accident may be prevented. |
