Examples On How To Connect, Configure And Set Ct Inputs For Most Commonly Used Ct Connections - Hitachi Relion 670 Series Applications Manual

1MRK506375-UEN Rev. N
In this example, one IED includes both transformer and line protections and the line protection uses
the same CT as the transformer protection does. For both current input channels, the CT direction is
set with the transformer as reference object. This means that the direction Forward for the line
protection is towards the transformer. To look towards the line, the direction of the directional
functions of the line protection must be set to Reverse. The direction Forward/Reverse is related to
the reference object that is the transformer in this case.
If the IED has sufficient number of analog current inputs, an alternative solution is shown in Figure
12. The same currents are fed to two separate groups of inputs and the line and transformer
protection functions are configured to the different inputs. The CT direction for the current channels
to the line protection is set with the line as reference object and the directional functions of the line
protection shall be set to Forward to protect the line.
IEC05000462 V2 EN-US
Figure 12:
4.2.2.4 Examples on how to connect, configure and set CT inputs for most
commonly used CT connections
Figure 13
Railway application RER670
Application manual
Transformer
Setting of current input
for transformer functions:
Set parameter
CTStarPoint with
Transformer as
reference object.
Correct setting is
"ToObject"
Example how to set CTStarPoint parameters in the IED
defines the marking of current transformer terminals commonly used around the world:
In the SMAI function block, you have to set if the SMAI block is measuring current or
voltage. This is done with the parameter: AnalogInputType: Current/Voltage. The
ConnectionType: phase -phase/phase-earth and GlobalBaseSel.
© 2017 - 2023 Hitachi Energy. All rights reserved
Transformer and
Line protection
IED
Setting of current input
for transformer functions:
Set parameter
CTStarPoint with
Transformer as
reference object.
Correct setting is
"ToObject"
Line
Reverse Forward
Definition of direction
for directional
line functions
Setting of current input
for line functions:
Set parameter
CTStarPoint with
Line as
reference object.
Correct setting is
"FromObject"
Section 4
Analog inputs
SEMOD55055-296 v7
49