Technical Data
4.1 General
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
571
4.1
General
4.1.1
Analog Inputs
Current Inputs
Current transformer requirements
Voltage inputs
Nominal frequency
f
N
50 Hz or 60 Hz (adjustable)
Nominal current
I
Nom
1 A or 5 A
Power Consumption per Phase and Earth Path
- at
I
N
= 1 A
Approx. 0.05 VA
- at
I
N
= 5 A
Approx. 0.3 VA
- for sensitive earth fault detection at 1A
Approx. 0.05 VA
Current Overload Capability per Current Input
- thermal (rms)
500 A for 1 s
150 A for 10 s
4 ·
I
N
continuous
- dynamic (pulse current)
1,250 A (half-cycle)
Current Overload Capability for Sensitive Earth Current Input
- thermal (rms)
300 A for 1 s
100 A for 10 s
15 A continuous
- dynamic (pulse current)
750 A (half-cycle)
1st condition:
For a maximum fault current the current transformers must not be
saturated under
steady-state conditions
2nd condition:
The operational accuracy limit factor n' must be at least 30 or a
non-saturated period t'
AL
of at least
1
/
4
AC cycle after fault inception
must be ensured
n'
≥
30
or
t'
AL
≥
1
/
4
cycle
3 rd Condition:
Maximum ratio between primary currents of current transformers at
the ends of the protected object
Nominal voltage U
N
80 V to 125 V (adjustable)
Measuring range
0 V to 218.5 V (rms)
Power consumption per phase
At 100 V
≤
0.1 VA
Voltage overload capability per phase
- thermal (rms)
230 V continuous
