Function Block; Functionality; Analog Channel Configuration - ABB RELION REX640 Technical Manual

Section 4
Protection functions
4.5.6.2
4.5.6.3
4.5.6.4
796

Function block

GUID-62285A87-57D2-4638-877F-0234D0EA46C7 V1 EN
Figure 433: Function block

Functionality

The positive-sequence undervoltage protection function PSPTUV is used to detect
positive-sequence undervoltage conditions. PSPTUV is used for the protection of
small power generation plants. The function helps in isolating an embedded plant
from a fault line when the fault current fed by the plant is too low to start an overcurrent
function but high enough to maintain the arc. Fast isolation of all the fault current
sources is necessary for a successful autoreclosure from the network-end circuit
breaker.
The function starts when the positive-sequence voltage drops below the set limit.
PSPTUV operates with the definite time (DT) characteristics.
The function contains a blocking functionality. It is possible to block function outputs,
the definite timer or the function itself.

Analog channel configuration

PSPTUV has one analog group input which must be properly configured.
Table 754: Analog inputs
Input
U3P
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 755: 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
Description
Three-phase voltages
Description
The function can work with any two voltage
channels connected but it is recommended to
connect all three voltage channels.
1MRS759142 C
REX640
Technical Manual