| 摘要 |
In one arm of the subscriber feed circuit (Ra, Rb, BS), an FET transistor (Tr1) is provided as a current-limiting element which is activated when a feed current limit value is reached in such a way that it limits the feed current. If the limitation operation lasts longer than a first time period, the feed current circuit is interrupted in that the transistor is blocked. The transistor can be switched to the conductive condition only when a second, longer time period has elapsed which is adequate for cooling off. <IMAGE> |
