ABB RELION REX640 - 4.1.3 Three-phase voltage-dependent overcurrent protection PHPVOC (ANSI 51 V); 4.1.3.1 Identification; 4.1.3.2 Function block; 4.1.3.3 Functionality

4.1.3 Three-phase voltage-dependent overcurrent protection
PHPVOC (ANSI 51V)
4.1.3.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Three-phase voltage-dependent
overcurrent protection
PHPVOC 3I(U)> 51V
4.1.3.2 Function block
Figure 220: Function block
4.1.3.3 Functionality
The three-phase voltage-dependent overcurrent protection function PHPVOC
is used for single-phase, two-phase or three-phase voltage-dependent time
overcurrent protection of generators against overcurrent and short circuit
conditions.
PHPVOC starts when the input phase current exceeds a limit which is dynamically
calculated based on the measured terminal voltages. The operating characteristics
can be selected to be either inverse definite minimum time IDMT or definite time
DT.
PHPVOC contains a blocking functionality. It is possible to block function outputs,
timers or the function itself.
4.1.3.4 Analog channel configuration
PHPVOC has two analog group inputs which all must be properly configured.
Table 414: Analog inputs
Input Description
I3P Three-phase currents
U3P Three-phase voltages
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.
1MRS759142 F
Protection functions
REX640
Technical Manual
369