Mitsubishi Electric 800 Series, Instruction Manual, Page: 667 / 727

Measurement of main circuit voltages, currents and powers
666
PRECAUTIONS FOR MAINTENANCE AND INSPECTION
7.2
Measurement of main circuit voltages,
currents and powers
Since the voltages and currents on the inverter power supply and output sides include harmonics, measurement data
depends on the instruments used and circuits measured.
When instruments for commercial frequency are used for measurement, measure the following circuits with the instruments
given on the next page.
NOTE
• When installing meters etc. on the inverter output side
When the inverter-to-motor wiring length is large, small-capacity models, the meters and CTs may generate heat due to line-
to-line leakage current. Therefore, choose the equipment which has enough allowance for the current rating.
To measure and display the output voltage and output current of the inverter, it is recommended to use the terminal AM and
FM output functions of the inverter.
Ar
As
At
Vr
Vs
Vt
Au
Av
Aw
Vu
Vv
Vw
W21
V
U
V
W
Inverter
Three-phase
power supply
To the motor
Input voltage
Input current
Output voltage
Output current
R/L1
S/L2
T/L3
P/+ N/-
W11
W12
W13 W22
+
-