ABB RELION 620 Series Technical Manual page 375

1MAC504801-IB E
620 series ANSI
Technical Manual
Generator convention
Forward reactive power
+Q
Synchronous
Generator
motor
PF<0 (lead) PF>0 (lag)
Q2 Q1
(PF = -1.0)
Q3 Q4
-P
PF<0 (lag)
PF>0 (lead)
Induction Induction
motor generator
-Q
Reverse reactive power
I
E
GUID-F53A3D93-405B-4BC5-A098-E4B820F6AA67 V1 EN
Figure 171: Power factor quadrant
If the polarity of the voltage signal is opposite to the normal polarity, the correction can be
done by setting Voltage reversal to "Yes", which rotates the power factor vector by 180
degrees.
If the magnitude of all three phase currents or voltages are respectively less than Current
block value and Voltage block value settings, the power factor is set as unity that is 1.00
and the function is disabled internally.
The DISABLE input can be used to coordinate the correct operation during the start-up
situation. By activating the DISABLE signal, the power factor calculation is blocked.
Once the DISABLE signal is deactivated, the function remains blocked for additional time
duration as set through the setting Disable time.
Level detector 1
The Level detector 1 compares the calculated power factor to the set Pickup value. If the
power factor value goes below the set Pickup value in the direction as defined by Dir
pickup value, the Level detector sends an enabling signal to the Timer 1 module.
Level detector 2
The Level detector 2 compares the calculated power factor to the set Alarm value. If the
power factor value goes below the set Alarm value in the direction as defined by Dir alarm
value, the Level detector sends an enabling signal to the Timer 2 module.
(PF = -1.0)
(PF = 1.0)
+P -P
V
Section 4
Protection functions
Motor convention
Forward reactive power
+Q
Induction Induction
generator motor
PF<0 (lead) PF>0 (lag)
Q2 Q1
(PF = 1.0)
Q3 Q4
PF<0 (lag)
PF>0 (lead)
Synchronous
Generator
motor
-Q
Reverse reactive power
I
E V
+P
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