Figure. 5.2.1 - 52. Connections.
The following table presents the initial data of the connection.
Table. 5.2.1 - 7. Initial data.
PPha
hase curr
se current C
ent CTT
- CT primary: 100 A
- CT secondary: 5 A
R
Ring cor
ing core C
e CT in Input I02
T in Input I02
- I0CT primary: 10 A
- I0CT secondary: 1 A
LLoad (
oad (nominal)
nominal)
36 A
- the phase currents are connected to the I01 residual via a Holmgren connection
- the starpoint of the phase current CT's secondary current is towards the line
Phase CT scaling
Next, to scale the current to per-unit values, we have to select whether the basis of the phase CT
scaling is the protected object's nominal current or the CT primary value.
If the CT values are chosen to be the basis for the per-unit scaling, the option "CT nom. p.u." is selected
for the "Scale meas to In" setting (see the image below).
Figure. 5.2.1 - 53. Setting the phase current transformer scalings to CT nominal.
A
AQ
Q-M215
-M215
Instruction manual
Version: 2.04
55
