With the Slope 1, you avoid an overfunction of the differential protection with low-current external faults as
a consequence of current-transformer transmission faults (stationary and dynamic faults). The default setting
of 0.30 is sufficient for many applications.
Parameter: Intersection 2 Irest
•
Default setting (_:11041:103) Intersection 2 Irest = 2.50 I/Irated,obj
NOTE
If excessive current flows are cause to expect transmission problems for the current transformer, set Slope
2 to a higher value.
The parameter Intersection 2 Irest determines from which restraint current the Slope 2 begins. The
default setting 2.50 I/Irated,obj is a practical value.
Parameter: Slope 2
•
Default setting (_:11041:102) Slope 2 = 0.70
With the parameter Slope 2, an overfunction of the differential protection is avoided with high-current
external faults as a consequence of current-transformer transmission faults (for example, due to saturation). A
value greater than or equal to double the value of Slope 1 is practical. As the default setting, 0.70 was
selected.
[dwdifaus-030912-01.tif, 1, en_US]
Figure 7-66
Characteristic Curve with the Default Settings
Parameter: Starting detection
•
Default setting (_:11041:106) Starting detection = yes
Capacitor Bank Protection
7.8 Differential Protection for Capacitor Banks
1064 SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017
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