FANOX SIL-D00, User Manual

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If the option "Defined time" is selected for the curve setting, the unit behaves like an
instantaneous overcurrent unit. In this case, the unit Time delay is adjusted by using the
parameter "Time delay".
If a curve (inverse, very inverse or extremely inverse) is selected for the curve setting, the Time
delay depends on the curve, dial and tap settings.
If the unit operates as defined time, the function is activated at 100% of the set tap value, and it
deactivates at 95%.
If the unit operates with a curve, the function is activated at 110% of the set tap value, and it
deactivates at 100%.
The reset is instantaneous in both cases.
The activation time is accurate to ±5% or ±30ms, whichever is higher, of the theoretical activation
time.
The curves used are IEC 60255-151 and IEEE, which are described in their section.
4.3. Function 50N/G. Instantaneous neutral overcurrent.
This protection function can be set by using three parameters:
Group Description Minimum Maximum Step Unit Default
50N/G_1
50N/G_2
Instantaneous neutral overcurrent.
Permission - - Yes/No - No
Tap 0.10 30.00 0.01 I
nominal
1,00
Time delay 0.02 300.0 0.01 s 0,02
The Time delay is completely independent from the operating current that flows through the
equipment, so if the neutral current exceeds its predetermined value for an equal or greater
amount of time than this preset value, the protection function activates (trips) and does not reset
itself until the average value of the phase drops below the point of current tap.
The function activates at 100% of the preset input, and deactivates at 95%. The reset is
instantaneous.
The accuracy of the Time delay is equal to the preset time ±30 ms or ±0.5%