Measurement Of Main Circuit Voltages, Currents And Powers - Mitsubishi Electric FR-A500 Instruction Manual

6.1.9

Measurement of main circuit voltages, currents and powers

Measurement of voltages and currents
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.
3-phase
power
supply
Instrument
types
Note: Use an FFT to measure the output voltage accurately. A tester or general measuring instrument
cannot measure accurately.
Input voltage
Input current
W R 〈 L
Ar
11
Vr
W S 〈 L
As
12
Vs
W T 〈 L
At
13
Vt
P/+
+
Example of Measuring Points and Instruments
PRECAUTIONS FOR MAINTENANCE AND INSPECTION
Inverter
〉
U
Au
1
Vu
〉
V
Av
2
Vv
〉
W
Aw
3
Vw
N/–
V
-
212
W
21
To motor
W
22
:Moving-iron type
:Electrodynamometer type
:Moving-coil type
:Rectifier type
Output voltage
Output current