ABB Relion 620 Series - Phase Discontinuity Protection PDNSPTOC

4.4.1.10 Technical revision history
Table 547: NSPTOC Technical revision history
Technical revision Change
B Minimum and default values changed to 40
ms for the Operate delay time setting
C Step value changed from 0.05 to 0.01 for the
Time multiplier setting
D Internal improvement
E Internal Improvements
4.4.2 Phase discontinuity protection PDNSPTOC
4.4.2.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Phase discontinuity protection PDNSPTOC I2/I1> 46PD
4.4.2.2 Function block
Figure 321: Function block
4.4.2.3 Functionality
The phase discontinuity protection function PDNSPTOC is used for detecting
unbalance situations caused by broken conductors.
The function starts and operates when the unbalance current I
2
/I
1
exceeds the set
limit. To prevent faulty operation at least one phase current needs to be above the
minimum level. PDNSPTOC operates with DT characteristic.
The function contains a blocking functionality. It is possible to block the function
output, timer or the function itself, if desired.
4.4.2.4 Operation principle
The function can be enabled and disabled with the Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of PDNSPTOC can be described by using a module diagram. All the
modules in the diagram are explained in the next sections.
1MRS757644 H
Protection functions
620 series
Technical Manual
615