Max mode (coarse biasing):
Now these two mentioned formulas are combined in a way so that the y axle presents the differential
current measured and the x axle present the bias current calculated.
Figure. 5.4.10. - 103. Differential function characteristic, biased and non-biased.
In the characteristics the red line presents the allowed differential current in percentage in function of
measured biasing current of the differential protection. In this example the non-biased pick-up is set to
quite low what it would be in normal transformer application. Settings and ranges of the differential
protection are presented in the settings chapter.
The biasing characteristic is formed with following formulas:
AQ-T216
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
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