Operation Principle - ABB RELION REX640 Technical Manual

Section 5
Protection related functions
5.12.5
1170
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 1091: Special conditions
Condition
U3P connected to real measurements
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.

Operation principle

The function can be enabled and disabled with the Operation setting. The
corresponding parameter values are "on" and "off".
The operation of CRWPSCH can be described with a module diagram. All the
modules in the diagram are explained in the next sections.
IRV
BLK_IRV
U_AB
U_BC
U_CA
U3P U_A
U_B
U_C
CB_OPEN
CR
BLK_WEI1
BLK_WEI2
FF
BLOCK
GUID-C4A24567-8197-4F7D-938A-E6558236788C V1 EN
Figure 630: Functional module diagram
Current reversal logic
Current reversal logic is enabled by changing the value of the Reversal mode setting to
"On".
Description
The function can work with any two phases
connected but it is recommended to connect all
three voltage channels.
Current
OPR_IRV
reversal
logic
OPR_WEI
Weak end
ECHO
infeed
logic
CR
1MRS759142 C
REX640
Technical Manual