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III.14 Balanced and Unbalanced 3 Phase (3P3W or 3P4W) Load
System
In order to check if current of a system is balanced, press the button
twice to display the phasor diagram with the IUR displayed.
Balanced System
If a 3 phase load system is balanced, the parameters should be as following:
I1 = I2 = I3
The phase angle of phasors I2 and I1 (I2 ± I1) = ±120
The phase angle of phasors I3 and I2 (I3 ± I2)= ±120
In (current of neutral) = 0A
IUR = 0%
d0% = 0%
d2% = 0%
Unbalanced System
If the values are different from the numbers above, then we can say it is an
unbalanced load system. The magnitude of the difference can be used as an
indication of an unbalanced power source system. The larger the difference, the
more unbalanced the load is.
