YOKOGAWA WT210, User Manual, Page: 90 / 316

4-22
IM 760401-01E
Explanation
The efficiency of the device can be computed and shown on display C. When displaying
the efficiency, “ ” is displayed at the front of the value.
Computing Equation of Efficiency
• For the three-phase, three-wire model (760502)
Computes the efficiency by taking the active power (W1) measured on element 1
as the active power applied to the primary side of the inverter and the active power
(W3) measured on element 3 as the power consumed by the secondary side of the
inverter.
Inverter
Primary side
W1
Secondary side
W3
Output side
Equation
Efficency =
×
100(%)
W3
W1
• For the three-phase, four-wire model (760503)
Computes the efficiency by taking the active power (W2) measured on element 2
as the active power applied to the primary side of the inverter and the active power
(W1 and W3) measured on elements 1 and 3 as the power consumed by the
secondary side of the inverter.
Inverter
Primary side
W2
Secondary side
W1
Output side
W3
Equation
Efficency =
×
100(%)
W1+W3
W2
Note
If the denominator of the above equation is less than or equal to 0.0001% of the rated range,
computation overflow ( --oF-) is indicated.
4.9 Computing the Efficiency (Applies to WT230 Only)