ABB RELION RET670, Applications Manual

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Always be careful when connecting function blocks with a fast cycle
time to function blocks with a slow cycle time.
Remember to design the logic circuits carefully and always check the
execution sequence for different functions. In other cases, additional
time delays must be introduced into the logic schemes to prevent errors,
for example, race between functions.
17.7 Fixed signal function block FXDSIGN
IP15080-1 v2
17.7.1 Identification
SEMOD167904-2 v2
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Fixed signals FXDSIGN - -
17.7.2 Application
M15322-3 v12
The Fixed signals function (FXDSIGN) has nine pre-set (fixed) signals that can be
used in the configuration of an IED, either for forcing the unused inputs in other
function blocks to a certain level/value, or for creating certain logic. Boolean, integer,
floating point, string types of signals are available.
One FXDSIGN function block is included in all IEDs.
Example for use of GRP_OFF signal in FXDSIGN
The Restricted earth fault function REFPDIF (87N) can be used both for auto-
transformers and normal transformers.
When used for auto-transformers, information from both windings parts, together with
the neutral point current, needs to be available to the function. This means that three
inputs are needed.
Section 17
1MRK 504 163-UUS A
Logic
850 Transformer protection RET670 2.2 ANSI
Application manual