ABB RELION Series Technical Manual page 84

Section 3
Basic functions
78
I
n
K
×
r
I
pr
RSV
=
f
n
GUID-6A480073-5C35-4319-8B38-402608D4C098 V2 EN
RSV
I
n
I
pr
f
n
K
r
In this example, the value is as calculated using the equation.
150 A
150 mV
×
80 A
= . 5 625
50 Hz
GUID-13DE42A0-29C0-4FE0-B00B-1215B37E3B7B V2 EN
With this information, the protection relay's Rogowski sensor settings can be set.
Table 29: Example setting values for rogowski sensor
Setting
Primary current
Rated secondary value
Nominal current
Unless otherwise specified, the Nominal Current setting should
always be the same as the Primary Current setting.
If the ratio of the application nominal current I
becomes higher, and the rated secondary value needs to be set higher than 46.875 mV/
Hz, the highest value that the relay is able to measure before the current sensor input
is saturated is smaller than the maximum setting value of the current protection.
Table 30: Maximum current protection setting values
Application nominal current
(I )
n
...1250 A
1250...2500 A
2500...4000 A
Rated Secondary Value in mV/Hz
Application nominal current
Sensor-rated primary current
Network nominal frequency
Sensor-rated voltage at the rated current in mV
mV
Hz
Value
150 A
5.625 mV/Hz
150 A
n
Rated secondary value with 80 A/
0.150 V at 50 Hz
1.000...46.875 mV/Hz
46.875...93.750 mV/Hz
93.750...150.000 mV/Hz
1MRS758755 A
and sensor-rated primary current I
Current protection maximum setting
value not to be exceeded
40 × I (Also the maximum of the
n
start value setting range)
20 × I
n
12.5 × I
n
REC615 and RER615
Technical Manual
(Equation 1)
(Equation 2)
pr