CHAPTER 2: PRODUCT DESCRIPTION
SPECIFICATIONS
L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
2-31
2
2.6.1 Protection elements
The operating times include the activation time of a trip rated form-A output contact unless otherwise indicated. FlexLogic
operands of a given element are 4 ms faster. Take this into account when using FlexLogic to interconnect with other
protection or control elements of the relay, building FlexLogic equations, or interfacing with other intelligent electronic
devices (IEDs) or power system devices via communications or different output contacts. If not specified, the operate times
given here are for a 60 Hz system at nominal system frequency. Operate times for a 50 Hz system are 1.2 times longer.
PHASE DISTANCE
Characteristic:
mho (memory polarized or offset) or quad (memory polarized or non-directional), selectable indi-
vidually per zone
Number of zones:
5
Directionality:
forward, reverse, or non-directional
Reach (secondary
Ω
):
0.02 to 500.00
Ω
in steps of 0.01
Reach accuracy:
Zone 1:
±5% including the effect of CVT transients up to an SIR of 30 and ±7% for 30<SIR< 60 at RCA
angle
Zones 2 to 5:
±5% for steady fault conditions
Distance:
Characteristic angle:
30 to 90° in steps of 1
Comparator limit angle:
30 to 90° in steps of 1
Directional supervision:
Characteristic angle:
30 to 90° in steps of 1
Limit angle:
30 to 90° in steps of 1
Right blinder (Quad only):
Reach:
0.02 to 500
Ω
in steps of 0.01
Characteristic angle:
60 to 90° in steps of 1
Left Blinder (Quad only):
Reach:
0.02 to 500
Ω
in steps of 0.01
Characteristic angle:
60 to 90° in steps of 1
Time delay:
0.000 to 65.535 s in steps of 0.001
Timer accuracy:
±3% of operate time or ±1/4 cycle (whichever is greater)
Current supervision:
Level:
line-to-line current
Pickup:
0.050 to 30.000 pu in steps of 0.001
Dropout:
97 to 98%
Memory duration:
5 to 25 cycles in steps of 1
VT location:
all delta-wye and wye-delta transformers
CT location:
all delta-wye and wye-delta transformers
Voltage supervision pickup (series compensation applications):
0 to 5.000 pu in steps of 0.001