Siemens 7SC80 Manual page 547

Ground Fault Pickup for All Types of Ground Faults (Inverse Time Characteristic)
User-defined characteristic (defined by a maximum of 20 value pairs of current and time delay in direction
measurement method "cos phi and sin phi")
Pickup current 51Ns
for sensitive 1 A transformer
for sensitive 5 A transformer
for normal 1 A transformer
for normal 5 A transformer
Time multiplier T
Pickup threshold
Dropout ratio
Measurement tolerance
sensitive
non-sensitive
Operating time tolerance in linear range
Trip Time Characteristics according to IEC
Acc. to IEC 60255-3 or BS 142, Sectiont 3.5.2 (see also
The tripping times for Ι/Ι
Pickup threshold
SIPROTEC Compact, 7SC80, Manual
E50417-G1140-C486-A8, Edition 07.2017
51Ns
for Ι = 1 A
Nom
for Ι = 5 A
Nom
for Ι = 1 A
Nom
for Ι = 5 A
Nom
≥ 20 are identical with those for Ι/Ι
51Ns
4.15 Ground Fault Detection (Sensitive/Insensitive)
0.001 A to 1.400 A
0.005 A to 7.000 A
0.05 A to 4.00 A
0.25 A to 20.00 A
0.10 s to 4.00 s or ∞ (disabled)
approx. 1.10 · Ι
51Ns
approx. 1.05 · Ι for Ι
51Ns 51Ns
3 % of setting value or 1 mA
3 % of setting value or 5 mA
for setting values < 10 mA ca. 20 %
3 % of setting value or 15 mA
3 % of setting value or 75 mA
7 % of reference (calculated) value for
2 ≤ Ι/Ι ≤ 20 + 2 % current tolerance, or 70 ms
51Ns
Figure 4-1 and Figure
= 20
EEp
approx. 1.10 · Ι
Technical Data
Increments 0.001 A
Increments 0.005 A
Increments 0.01 A
Increments 0.05 A
Increments 0.01 s
> 50 mA
4-2)
EEp
547