Power factor calculation is done similarly to the Cosine phi calculation but the polarity is defined by the
reactive power direction. Therefore, the power factor is calculated with the following formula:
Onl
Only line
y line-t
-to-line v
o-line volta
oltages a
ges avvailable
ailable
If the line-to-line voltages are measured but the zero sequence voltage is not measured or is not
otherwise known, the three-phase power calculation is based on Aron’s theorem:
Both cos(φ) and tan(φ) are calculated in the same way as in the line-to-neutral mode.
Troubleshooting
Check the "Troubleshooting" section in chapters “Current measurement and scaling” and “Voltage
measurement and scaling” for more information. Most power and energy measurement problems are
usually related to the same issues (i.e. wiring errors, wrong measurement modes, faulty frequency
settings, etc.).
Settings
Table. 5.2.3 - 35. Power and energy measurement settings
Name
Range
Step
Default
Description
3ph active
energy
measurement
0: Disabled
1: Enabled
-
0:
Disabled
Enables/disables the active energy measurement.
A
AQ
Q-M255
-M255
Instruction manual
Version: 2.06
© Arcteq Relays Ltd
IM00020
43
Summary of Contents for AQ-M255
Page 1: ...AQ M255 Motor protection IED Instruction manual...
Page 2: ......
