1MRS755225
Transformer Terminal
Technical Reference Manual, General
RET 54_
37
The indication of a low auxiliary voltage (ACFail) is available in the transformer
terminal configuration environment and can be connected to any signal output of the
RET 54_. The auxiliary voltage indication in the transformer terminal configuration
is as follows:
RET 541: PS1_4_ACFail
RET 543: PS1_4_ACFail
RET 545: PS2_4_ACFail
5.1.5.3.
Overtemperature indication
The RET 54_ transformer terminal includes an internal temperature supervision
function. The power supply module issues an internal alarm signal when
overtemperature has been detected inside the terminal enclosure. The alarm signal
will be activated once the temperature inside the terminal enclosure increases to
+78
o
C (+75...+83
o
C). Overtemperature indication is available in the transformer
terminal configuration and can be connected to any signal output of the terminal.
The overtemperature indication input in the transformer terminal configuration is as
follows:
RET 541: PS1_4_TempAlarm
RET 543: PS1_4_TempAlarm
RET 545: PS2_4_TempAlarm
5.1.6.
Analog channels
The transformer terminal measures the analog signals needed for protection,
measuring, etc. via galvanically separated matching transformers. The RET 54_
transformer terminals are provided with the following matching transformers:
• 6 current and 3 voltage transformers:
CT1, CT2, CT3, CT4, CT5, CT6, VT1, VT2, VT3
• 7 current and 2 voltage transformers:
CT1, CT2, CT3, CT4, CT5, CT6, CT7, VT1, VT2
• 8 current and 1 voltage transformers:
CT1, CT2, CT3, CT4, CT5, CT6, CT7, CT8, VT1
Furthermore, the transformer terminal includes virtual analog channels (refer to
Section “Calculated analog channels” on page 42) for calculating the neutral
current, phase-to-phase voltage and residual voltage from phase currents and
voltages.
Each analog channel is separately configured with the Relay Configuration Tool.
Both the measuring unit for each analog channel and the type of signal to be
measured are to be configured.
