Rev. 06
21/99
If the option "Defined time" is selected for the curve setting, the unit behaves like an instantaneous
overcurrent unit. In this case, the unit operating time is set by the parameter "Operating time".
If a curve (inverse, very inverse or extremely inverse) is selected for the curve setting, the operating
time depends on the curve, dial and tap settings.
If the unit operates with defined time, the function is activated at 100% of the set tap value, and it
deactivates at 90%.
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 accuracy is ± 5% or ±30ms of the theoretical activation time, whichever is greater.
The curves used are IEC 60255-151 or ANSI-IEEE, which are described in the "Curves" section.
5.3.
50N Function. Definite time overcurrent
This protection function can be set by using three parameters:
Function
Description
Minimum
Maximum
Step
Unit
Default
50N
Definite time neutral overcurrent
Permission
-
-
Yes/No
-
No
Tap
0,20
20,00
0,01
Is
1,00
Operating time
0,05
300,00
0,01
s
0,20
The operating time 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 pre-set value, the protection function activates (trips) and does not reset itself until the
value of the phase drops below the point of current pick-up.
The function activates at 100% of the pre-set input, and deactivates at 90%. The reset is
instantaneous.
The accuracy of the operating time is equal to the pre-set time ±30ms or ±0.5% (greater of both).
Summary of Contents for SIA B
Page 7: ...www fanox com Rev 06 7 99 2 DIMENSIONS AND CONNECTION DIAGRAMS 2 1 Frontal view...
Page 8: ...www fanox com Rev 06 8 99 2 2 Case dimensions The dimensions are in mm Cut out pattern...
Page 9: ...www fanox com Rev 06 9 99 2 3 Connection diagram NOTE STRIKER 6 24 Vdc 0 1 W s...
Page 18: ...www fanox com Rev 06 18 99 Dimensions...
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