Section 3
REF615 variants
3.5.3
3.5.3.1
60
Functional diagrams
The functional diagrams describe the default input, output, alarm LED and function-
to-function connections. The default connections can be viewed with SMT and
changed according to the application requirements, if necessary.
The analog channels, measurements from CTs and VTs, have fixed connections
towards the different function blocks inside the IED's standard configuration.
Exceptions from this rule are the 12 analog channels available for the disturbance
recorder function. These channels are freely selectable and a part of the disturbance
recorder's parameter settings, thus not included in the SMT functionality.
The analog channels are assigned to different functions as shown in the functional
diagrams. The common signal marked with 3I represents the three phase currents.
The signal marked with I
connection of the phase current transformers.
Functional diagrams for protection
The following functional diagrams describe the IED's protection functionality in
detail and according to the factory set default connections in SMT.
represents the measured residual current via a summation
0
1MRS756378 D
REF615
Application Manual