Section 4
Analog inputs
4.2.2.5
Example on how to connect a wye connected three-phase CT set to the IED
Figure
21
gives also an overview of the actions which are needed to make this measurement available to the
built-in protection and control functions within the IED as well.
A
B
CT 600/5
Star Connected
Protected Object
ANSI13000002 V2 EN-US
Figure 21:
Wye connected three-phase CT set with wye point towards the protected object
64
It is recommended to:
•
use 1A rated CT input into the IED in order to connect CTs with 1A and 2A
secondary rating
•
use 5A rated CT input into the IED in order to connect CTs with 5A and 10A
secondary rating
gives an example about the wiring of a wye connected three-phase CT set to the IED. It
For correct terminal designations, see the connection diagrams valid for the
delivered IED.
C
I_A
I_B
I_C
IED
1
2
3
1MRK 505 337-UUS A
SEMOD55055-352 v9
4
SMAI_20
ANSI3000002-2-en.vsd
Application manual