Measuring Voltage And Current - Mitsubishi Electric FR-K-400-U Instruction Manual

8-3 Measuring Voltage and Current
Since the primary and secondary voltage and current contain high frequency, data may differ depend-
ing upon the instrument used and the circuit t o be measured.
I f you use a measuring instrument for commercial frequency, select one listed i n Table 3 and measure
the circuit as shown i n Fig.
5
Variation o f the indicated value are shown i n Fig. 6. However, even measuring instruments of the same
accuracy may be inconsistent because of differences i n factors such as manufacturer, model type or
year made, etc.
FR-K
Inverter
7
Fig.
5
Points t o be Measured and Examples of Measuring Instruments
Example: Output voltage of inverter
Motor rating:
3.7 kW
4P
FR-K.3700-U Inverter
Take the indicated value of
rectifier type voltmeter as
100%.
4
Rectifier type
k
Moving-iron type
Electrothermic type
Fig.
6
Variation of Indicated Value Depending on the Type of the
Measuring Instrument