Meters And Measuring Methods - Mitsubishi Electric FR-A700 Instruction Manual

Troubleshooting
7.7

Meters and measuring methods

Since voltages and currents in the primary and secondary side of the inverter include harmonics,
different meters indicate different measured values. When making measurement with the me-
ters designed for commercial frequency, use the following measuring instruments and circuits:
When installing meters etc. on the inverter output side
When the inverter-to-motor wiring length is large, especially in the 400 V class, 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.
When measuring and indicating the output voltage and output current of the inverter, it is rec-
ommended to utilize the AM-5 and CA-5 terminal output function of the inverter.
power supply
Instrument types
Fig. 7-7: Measurements at the main circuit
FR-A700 EC
3-phase
Inverter
Meters and measuring methods
To the motor
Moving-iron type
Electro dynamometer type
Moving-coil type
Rectifier type
I001300E
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