GE D90 Plus Instruction Manual page 410

PROTECTION FLEXLOGIC™
400
Element
Source current
Source power
Source voltage
Hysteresis
Range: 0.1 to 50.0% in steps of 0.1
Default: 3.0%
This setting controls the element pickup and dropout relation by specifying the width of
the hysteresis loop as a percentage of the pickup value. It should be noticed that both
the operating signal and the pickup threshold can be negative facilitating applications
such as reverse power alarm protection. The FlexElement™ can be programmed to work
with all analog actual values measured by the relay.
Figure 353: Direction, pickup, and hysteresis relation
Delta T Units
Range: milliseconds, seconds, minutes
Default: milliseconds
This setting specifies the time unit for the
comparison mode.
Delta T
Range: 20 to 86400 in steps of 1
Default: 20
This setting specifies duration of the time interval for the rate of change mode of
operation. It is applicable only in the delta comparison mode.
Pickup Delay
Range: 0.000 to 65.535 seconds in steps of 0.001
Default: 0.000 seconds
This setting specifies the pickup delay of the FlexElement™.
Reset Delay
Range: 0.000 to 65.535 seconds in steps of 0.001
Default: 0.000 seconds
This setting specifies the reset delay of the FlexElement™.
Base unit
Maximum nominal primary RMS value of the +IN and –IN inputs
Maximum value of the product of the voltage and current base
values for the +IN and –IN inputs.
Maximum nominal primary RMS value of the +IN and –IN inputs.
setting. It is applicable only in the delta
Delta T
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 7: PROTECTION