Transformer wiring safety knowledge - Database & Sql Blog Articles

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

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First, preventive measures (1) In the experimental report should also clearly indicate the test method, test results, wiring methods of the same name of the current transformer. (2) Protection setting personnel can clearly specify the current transformer polarity of the special line on the fixed value list. For example, based on the bus line, the fault current flows from the bus line to the line is positive, and the device should operate reliably; The line flow to the bus is negative and the device should not operate. (3) In the production practice, due to the polarity and wiring of the current transformer, the protection device is malfunctioned and rejected, and the power failure caused by this occurs sometimes. The experimenter should pay attention to the study of theoretical knowledge and familiarity with each other. The principle of protection, fully understand the importance of current transformer polarity and wiring, and strictly follow the design drawings. (4) According to the quality management requirements, the equipment acceptance form used in equipment acceptance should add items that are usually easily overlooked but important, such as the test method of the same name of the current transformer, the test result, and the correct wiring method. Second, the polarity judgment and the connection of the secondary line Take the double-turn transformer differential protection wiring as an example, briefly explain how to judge the polarity of the current transformer and the correct secondary wiring of the zero-sequence current transformer. In the experimental report of the newly installed equipment, often all kinds of experimental technical data are very complete, all the tests are qualified, but there is no record of current transformer polarity and wiring, because the acceptance work is not careful, and the polarity of the transformer and Some errors in the wiring are not easy to be found. As a result, after the equipment is running, problems are exposed under certain conditions, causing protection misoperation or refusal.