ROOTECH Accura 2300 Front, User Manual

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Chapter 5 Measurement Description Accura 2300/2350 User Guide
Page 194
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V
A
V
B
V
C
V
A
= V
1
– V
n
V
B
= V
2
– V
n
V
C
= V
3
– V
n
V
2
V
3
V
1
V
n
V
N
Virtual line-to-neutral
voltage calculation
▶
Calculate virtual line-to-neutral voltage based on
the virtual neutral voltage.
V
A
= V
1
- Vn
V
B
= V
2
- Vn
V
C
= V
3
- Vn
Residual voltage
calculation Residual voltage of virtual line-to-neutral voltages is
0.
Line-to-line voltage
calculation V
AB
= V
A
- V
B
= V
1
– V
2
V
BC
= V
B
- V
C
= V
2
– V
3
V
CA
= V
C
- V
A
= V
3
– V
1
Measured values provided
Item Line-to-neutral voltage[rms] Line-to-line voltage[rms] Current[rms] Active Power
Phase A V
A
V
AB
I
A
(I
1
) P
A
= V
A
* I
A
* PF
A
Phase B V
B
V
BC
I
B
(I
2
) P
B
= V
B
* I
B
* PF
B
Phase C V
C
V
CA
I
C
(I
3
) P
C
= V
C
* I
C
* PF
C
Average/ Total (V
A
+V
B
+V
C
)/3 (V
AB
+V
BC
+V
CA
)/3 (I
A
+I
B
+I
C
)/3 P
A
+P
B
+P
C
Since there is no actual neutral point in the 3-phase 3-wire voltage connection, only the line-to-line voltage and
the total power can be known, and the actual voltage and the electric power for each phase cannot be known.
However, it is possible to obtain the virtual center point at which the residual voltage of the 3-phase voltage
becomes zero, and regard it as the neutral point, thereby obtaining the voltage per phase and the power per
phase.