System And Station Data - Block 01 - Siemens SIPROTEC 7SD600 System Manual

6
Operating instructions
Numerical line differential protection SIPROTEC 7SD600 V3.0
6.3.3

System and station data - Block 01

The device requires some system and station data.
0 1 S Y S T E M
A
D A T A
The rated frequency of the system is the first setting
in this block. The default value 50 Hz need only be
changed if the system frequency is 60 Hz.
0 1 S Y S T E M
A
5 0 H z
+
6 0 H z
The primary rated current of the protected plant (addr.
01 INLn)and the primary rated current of the current
transformer (addr. 01 IW PRI)can be set to the same
value in most cases. The correct setting of the rated
current of the transformer is a prerequisite for calcula
ting and displaying the primary measured current va
lues (see also section 6.4.4). Specification of the
rated current of the protected plant allows opti
mum adaptation of the characteristic of the diffe
rential protection to the protected plant because
the pick-up thresholds and shape of the characte
ristic are related to this rated current when set
correctly.
The two rated currents should not differ by more than
a factor 4.
6 - 8
System manual Order no. E50417-G1176-C069-A1
[1100]
Start of the block "System data"
"
[1101]
Rated frequency of the system 50 or 60 Hz
B
Example:
Rated current of the protected plant: 1000 A
Current transformer rated current:
The device then refers pick-up thresholds and shape
of characteristic to a current which corresponds to
1000 A primary. The characteristic refers to 1000 A
primary as a result.
Both parameters must be set to the same at both
ends of the line. If the primary transformer rated cur
rents are different, they must be made equal by con
necting interposing at the end of the line with the lo
wer rated current. See section 5.2.4.4 for details.
2000 A
Siemens AG January 1999