Technical Data
4.15 Earth fault detection in a non-earthed system
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
613
4.15
Earth fault detection in a non-earthed system
Pickup/Tripping
Phase Determination
Determination of Direction
1)
Sensitive earth current input independent from
I
N
Displacement voltage 3U
0
>
1 V to 150 V
Increments 1 V
Delay T
Sens.E/F
0.00 s to 320.00 s
Increments 0.01 s
Optional trip with
additional delay time T
Sens.E/F TRIP
0.00 s to 320.00 s
Increments 0.01 s
Measuring tolerance
5 % of set value
Time tolerance
1 % of setting value or 10 ms
The set times are pure delay times.
Measuring principle
Voltage measurement phase-earth
Earth fault phase U
ph min
10 V to 100 V
Increments 1 V
Healthy phases U
ph max
10 V to 100 V
Increments 1 V
Measuring tolerance
5 % of set value
Measuring principle
Real/reactive power measurement
Pickup value
I
>
Sens.E/F
0.003 A
Increments 0.001 A
Angle correction for toroidal current transformer
0.0° to 5.0°
in 2 steps
Increments 0.1°
Measuring tolerance
10 % of set value
for tan
ϕ
≤
20 (for real power)
