ABB RELION REX640 Technical Manual page 1347

1MRS759142 F
continue to rotate after the primary supply voltage is switched off. Re-energizing
the motor immediately can result in catastrophic failure.
MSVPR gives permissive output when the remanent voltage of the motor reaches
a safe level to re-energize. Supervision can be selected for one-phase or for three-
phase operation. MSVPR can also adapt to a frequency range of 10...70 Hz.
The function contains a blocking functionality. It is possible to block the function
output, timer or the function itself.
6.8.4 Analog channel configuration
MSVPR has one analog group input which must be properly configured.
Table 1294: Analog inputs
Input
U3P
There are a few special conditions which must be noted with the configuration.
Table 1295: 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.
6.8.5 Operation principle
The function can be enabled and disabled with 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.
REX640
Technical Manual
See the preprocessing function blocks in this document for the possible
signal sources.
Supervision functions
Description
Three-phase voltages
Description
The function can work with one voltage chan-
Phase supervision is set
nel connected when
to "A or AB", "B or BC" or "C or CA".
The function requires that all three voltage
channels are connected if
is set to "A&B&C or AB&BC&CA".
Operation setting. The
Phase supervision
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