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4.6.1.4
Analog channel configuration
FRPFRQ has one analog group input which must be properly configured.
Table 879: Analog inputs
Input
Description
U3P
Three-phase voltages
See the preprocessing function blocks in this document for the possible
signal sources.
There are a few special conditions which must be noted with the configuration.
Table 880: Special conditions
Condition
Description
U3P connected to real measurements
The function requires that at least one phase
or phase-to-phase voltage channel is connec-
ted.
Improper analog channel configuration causes a validation error if the analog
channels are not completely configured or they do not match with certain settings.
For troubleshooting, check the contents of this chapter and also the preprocessing
blocks in this document. The configuration can be written to the protection relay
once the mismatch is corrected.
4.6.1.5
Operation principle
The function can be enabled and disabled with the
Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of FRPFRQ can be described using a module diagram. All the modules
in the diagram are explained in the next sections.
BLOCK
Operate
logic
Freq>/<
detection
df/dt
detection
Blocking
logic
OPR_OFRQ
ST_FRG
ST_OFRQ
START
OPERATE
ST_UFRQ
OPR_FRG
OPR_UFRQ
U3P
dF/dt
F
Figure 514: Functional module diagram
1MRS759142 F
Protection functions
REX640
Technical Manual
921