| 摘要 |
The invention relates to a method and a device for protecting and monitoring multiphase receivers, coupled in a star, whose star node is not linked to the star node of the source. The method consists in measuring the voltage across the terminals of one or more of the phases of a receiver or between the star node of a receiver and the star node of the source, in calculating the derivative thereof, in taking into account complementary external parameters of all kinds, in comparing these values with reference values and in operating on the receiver or the procedure which it is implementing as soon as an anomalous change in parameters is detected or as soon as one of the voltage values deviates from the reference value by a specified threshold. The device for protection consists: of devices for electrical isolation 1, and for stray voltage elimination 2, which are connected to a multiplexer 3 itself connected to a computer 7 through an amplitude matching 4, a root-mean-square value converter 5, an analogue/digital converter 6 and a phase comparator 8. Main application: protection of the resistors of high-power electric ovens. <IMAGE>
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