| 摘要 |
PURPOSE: To take thermal history into consideration by providing a trip device with a means of calculating a temperature difference between two areas and the means of changing a trip function time delay to be inversely proportional to a temperature difference when a circuit breaker is closed. CONSTITUTION: A temperature-measuring means contains a temperature- measuring means 18 in a cold area in a case 10 and a temperature measuring means 22 in a hot area in the case near a connecting terminal 12. A trip device is provided with the means of calculating a temperature difference DT deg. between the cold area and the hot area and the means of changing a time delay for trip function, to be inversely proportional to the measured temperature difference DT deg., when a circuit breaker is closed. In this way, a device for which the thermal history of a separated system is taken into consideration is obtained. |
