ABB Relion 611 Series, Technical Manual

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4.5 Voltage protection
4.5.1 Three-phase overvoltage protection PHPTOV
4.5.1.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Three-phase overvoltage protection PHPTOV 3U> 59
4.5.1.2 Function block
GUID-871D07D7-B690-48FD-8EA1-73A7169AE8BD V2 EN
Figure 120: Function block
4.5.1.3 Functionality
The three-phase overvoltage protection function PHPTOV is applied on power
system elements, such as generators, transformers, motors and power lines, to protect
the system from excessive voltages that could damage the insulation and cause
insulation breakdown. The three-phase overvoltage function includes a settable value
for the detection of overvoltage either in a single phase, two phases or three phases.
PHPTOV includes both definite time (DT) and inverse definite minimum time
(IDMT) characteristics for the delay of the trip.
The function contains a blocking functionality. It is possible to block function outputs,
timer or the function itself, if desired.
4.5.1.4 Operation principle
The function can be enabled and disabled with the Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of PHPTOV can be described using a module diagram. All the modules
in the diagram are explained in the next sections.
Section 4
1MRS757454 D
Protection functions
252 611 series
Technical Manual