| 摘要 |
The invention relates to an overcurrent relay 5 with means to increase the threshold value @ for tripping of the relay when electrical apparatus, for example power transformers and cables, are connected to a network. The increase in the threshold value @ is arranged to take place instantaneously upon connection of the apparatus and a threshold value control device (9) is provided to ensure that after the instantaneous increase, the threshold value decreases exponentially to a normal threshold value. <IMAGE> |
