Operation Principle - ABB RELION REX640 Technical Manual

Section 6
Supervision functions
6.8.5
1242
There are a few special conditions which must be noted with the configuration.
Table 1178: 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 MSVPR can be described with a module diagram. All the modules
in the diagram are explained in the next sections.
U_A_AB
U_B_BC
U3P
U_C_CA
BLOCK
GUID-25EAD716-E693-4E14-87A0-B4486D4C0A12 V1 EN
Figure 676: Functional module diagram
Level detector
The Voltage selection setting is used for selecting the phase-to-earth or phase-to-
phase voltages for supervision.
The voltage measurement can adapt the frequency to a range of 10...70 Hz.
Level detector supports one- or three-phase operation. Selection can be made with
setting Phase supervision.
Description
The function can work with one voltage channel
connected when
AB", "B or BC" or "C or CA".
The function requires that all three voltage
channels are connected if
to "A&B&C or AB&BC&CA".
Timer
Level
t
detector
1MRS759142 C
Phase supervision is set to "A or
Phase supervision is set
U_LOW
REX640
Technical Manual