S&C IntelliRupter PulseCloser Manual page 52

Protection Setup
52 S&C Instruction Sheet 766-530
Initial Trip – Additional Features Section
Intelligent Fuse Saving
The Intelligent Fuse Saving (IFS) element is only active in the Initial Trip state. When
the IFS element (Phase and/or Ground) picks up and starts timing for a minimum of
2 cycles, and current goes below both the Phase Minimum Trip and Ground Minimum
Trip settings for at least two cycles, the IFS elements are turned off for the duration of
the O/C Reset and IFS Sequence Reset Timers. See Figure 36.
Figure 36. The Setup>Protection>General Profile 1>Direction 1 Current>Initial Trip>Additional
Features screen.
If another fault occurs within the sequence reset time window, only the base curve
is active and it would time and potentially trip the IntelliRupter fault interrupter, which
then enters the test sequence as usual. The IntelliRupter fault interrupter will stay in its
Initial Trip state unless it trips on the base curve.
After the sequence reset time expires and no elements have been picked up, the IFS
mode is re-initiated and the IntelliRupter fault interrupter is reset to the Initial Trip state.
Inverse Segment
Select the fuse type and speed to be saved. Select from the drop-down list of inverse curve
names or select the None option. This curve applies to the enabled Phase or Ground
IFS element. If the None option is selected, only the Definite Time settings will be used.
Phase check box—Select this check box to specify the phase overcurrent inverse curve.
Ground check box—Select this check box to specify the ground overcurrent inverse
curve.