3.17
Preprocessing blocks
3.17.1
Phase current preprocessing ILTCTR
3.17.1.1
Identification
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Phase current preprocessing
ILTCTR
ILTCTR
ILTCTR
3.17.1.2
Function block
Figure 88: Function block
3.17.1.3
Functionality
The phase current preprocessing function ILTCTR is used for setting up the three
phase current measurement channels. The input channels for ILTCTR are either
physical hardware or IEC 61850-9-2 sampled value channels. The output
I3P
channel of ILTCTR can be connected to different applications which require 3 phase
current and positive- and negative-sequence current. The output
IRES_CLC
can be
connected to functions using the calculated residual current.
The current transducer selection can be made by setting
Current input type to
"Current trafo" for conventional CT or to "Current sensor" for current sensor type.
The sensor's or the CT's primary rated current can be set using
Primary current
setting. The setting
Secondary current defines the nominal current of the CT's
secondary winding. This is used as a reference to scale the measurements
accordingly. These settings also affect the scaling of the calculated residual current.
Current magnitude correction of an external CT can be made using settings
Amplitude Corr A, Amplitude Corr B and Amplitude Corr C.
Current angle correction of an external CT can be made using settings
Angle Corr A,
Angle Corr B and Angle Corr C.
Rated secondary Val setting defines the ratio for sensor use. This value multiplied
by the
Rated frequency setting (under Configuration > System) gives the sensor's
nominal voltage corresponding to the sensors' primary rated current.
Reverse polarity setting is used to reverse the polarity of phase CTs.
1MRS759142 F
Basic functions
REX640
Technical Manual
191