CHAPTER 6: SETPOINTS
S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
6–39
Multiply
Range: 0.01 to 30.00 in steps of 0.01
Default: 1.00
This setting provides selection for Time Dial Multiplier by which the times from the
inverse curve are modified. For example if an ANSI Extremely Inverse curve is selected
with TDM = 2, and the fault current was 5 times bigger than the PKP level, the operation
of the element will not occur before a time elapse of 495 ms from pickup.
Initialization
Used after specifying a curve to use as a base for a custom FlexCurve™ (see
Select
Curve
and
Multiply
above). When the
Initialize FlexCurve
button is clicked, the pickup
settings will be populated with values specified by the curve selected in this setting.
1.03 × Pickup, ..., 20.00 × Pickup
Range: 0 to 65535 ms in steps of 1
Default: 0 ms
These settings specify the time to operate at the following pickup levels 1.03 to 20.00.
This data is converted into a continuous curve by linear interpolation between data
points. To enter a custom FlexCurve™, enter the operate time for each selected pickup
point.
NOTE
NOTE:
Each FlexCurve can be configured to provide inverse time characteristic to more than one
Time Overcurrent Element. However, for computation of the curve operating times, one
must take into account the setting of the Time Delay Multiplier from the FlexCurve menu,
and the Time Delay Multiplier setting from TOC menu. The true TDM applied to the TOC
element when FlexCurve is selected is the result from the multiplication of both TDM
settings. For example, for FlexCurve Multiplier = 5, and Phase TOC Multiplier = 2, the total
Time Dial Multiplier will be equal to 10. To avoid confusion, it is suggested to keep the
multiplier from the TOC menu equal to 1, and change only the multiplier from the selected
FlexCurve. This way, one can see from the FlexCurve setup, the curve operating times as
related to the multiples of pickup.