ABB RELION REX640 Technical Manual page 483

1MRS759142 F
There are a few special conditions which must be noted with the configuration.
Table 556: Special conditions
Condition
URES calculated
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.
4.2.3.5 Operation principle
The function can be enabled and disabled with the
corresponding parameter values are "On" and "Off".
The operation of INTRPTEF can be described with a module diagram. All the
modules in the diagram are explained in the next sections.
Figure 273: Functional module diagram
Level detector
The Level detector module is used only when selected
EF". The module compares the measured residual voltage to the set
value. If the measured value exceeds the set
the exceeding of the value to the Fault indication logic.
Transient detector
The Transient detector module is used for detecting transients in the residual
current and residual voltage signals.
The transient detection is supervised with a settable current threshold. With
a special filtering technique, the setting
REX640
Technical Manual
See the preprocessing function blocks in this document for the possible
signal sources.
Io
IRES
Transient
Uo
detector
URES
detector
BLOCK
Description
The function requires that all three voltage
channels are connected for calculating the re-
sidual voltage. Setting
be "Wye" in that particular UTVTR.
Fault
indication
logic
Level
Voltage start value, the module reports
Min operate current is based on the
Protection functions
VT connection must
Operation setting. The
Timer 1
OPERATE
t
START
Timer 2
BLK_EF
Operation mode is "Transient
Voltage start
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