ABB RELION 620 Series Technical Manual page 751

1MRS757644 F
620 series
Technical Manual
GUID-9C7C3D36-0158-47B5-902B-E4F22830C03E V1 EN
Figure 379: Operating area of DQPTUV function
Quadrant II Generator produces active power, but draws reactive power (under-excited)
Quadrant III Generator produces both active and reactive power
The power direction can be reversed by setting Pol reversal to "True".
Timer
Once activated by both Under voltage detection and Reactive power monitoring
module, the Timer activates the START output. The Timer characteristic is according
to DT. When the operation timer has reached the value set by Operate delay time, the
OPERATE output is activated. If the fault disappears before the module operates, the
Timer is reset instantaneously.
The Timer calculates the start duration value "START_DUR" which indicates the
percentage ratio of the start situation and the set operating time. The value is available
through the Monitored data view.
Blocking logic
There are three operation modes in the blocking function. The operation modes are
controlled by the BLOCK input and the global setting Configuration/System/
Blocking mode which selects the blocking mode. The BLOCK input can be controlled
by a binary input, a horizontal communication input or an internal signal of the
protection relay's program. The influence of the BLOCK signal activation is
preselected with the global setting Blocking mode.
Section 4
Protection functions
745