Signals; Settings - ABB RELION REX640 Technical Manual

Section 4
Protection functions
4.5.1.8
4.5.1.9
Table 709: PHPTOV Group settings (Basic)
Parameter
Start value
Time multiplier
Operate delay time
Operating curve type
772
• The defective operation of the automatic voltage regulator when the generator is
in isolated operation.
• Operation under manual control with the voltage regulator out of service. A
sudden variation of load, in particular the reactive power component, gives rise to
a substantial change in voltage because of the inherent large voltage regulation of
a typical alternator.
• Sudden loss of load due to the tripping of outgoing feeders, leaving the generator
isolated or feeding a very small load. This causes a sudden rise in the terminal
voltage due to the trapped field flux and overspeed.
If a load sensitive to overvoltage remains connected, it leads to equipment damage.
It is essential to provide power frequency overvoltage protection, in the form of time
delayed element, either IDMT or DT to prevent equipment damage.

Signals

Table 707: PHPTOV Input signals
Name
U3P
BLOCK
Table 708: PHPTOV Output signals
Name
OPERATE
START

Settings

Values (Range) Unit
0.05...1.60 xUn
0.025...15.000
40...300000 ms
5=ANSI Def. Time
15=IEC Def. Time
17=Inv. Curve A
18=Inv. Curve B
19=Inv. Curve C
20=Programmable
Type Default Description
SIGNAL - Three-phase voltages
BOOLEAN 0=False Block signal for activating the blocking mode
Type Description
BOOLEAN Operate
BOOLEAN Start
Step Default
0.01 1.10
0.005 1.000
10 40
15=IEC Def. Time
1MRS759142 C
Description
Start value
Time multiplier in IEC/ANSI IDMT curves
Operate delay time
Selection of time delay curve type
Technical Manual
REX640