Fixed Signal Function Block Fxdsign; Application - Hitachi Relion 670 Series Applications Manual

Section 15
Logic
IEC09000695 V2 EN-US
Figure 93:
IEC09000310 V2 EN-US
Figure 94:
The execution of different function blocks within the same cycle is determined by the order of their serial
execution numbers. Always remember this when connecting two or more logical function blocks in series.
15.7

Fixed signal function block FXDSIGN

15.7.1

Application

The Fixed signals function (FXDSIGN) has nine pre-set (fixed) output 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.
218
Example designation, serial execution number and cycle time for logic function
Example designation, serial execution number and cycle time for logic function that
also propagates timestamp and quality of input signals
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.
© 2017 - 2023 Hitachi Energy. All rights reserved
IEC09000695_2_en.vsd
IEC09000310-2-en.vsd
1MRK511407-UUS Rev. N
IP15080-1 v2
M15322-3 v16
Phasor measurement unit RES670
Application manual