摘要 |
Solid-state trip unit having a unit (29, 50, 48) for digital processing of signals emitted by current sensors (16). The digital processing system provides the long delay, short delay and instantaneous tripping functions and delivers a tripping order to the relay (14). An analog processing unit (70) is connected parallel with the digital processing unit to transmit an instantaneous tripping order to the relay (14). When the digital processing unit operates, the analog unit pick-up level is higher than the digital instantaneous tripping pick-up and this pick-up is reduced to a lower or equal value, if the digital unit is inactive.
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