Mitsubishi Electric fr-e700 series, Инструкция по эксплуатации

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Meters and measuring methods Troubleshooting
7 - 30
7.7 Meters and measuring methods
Since voltages and currents in the primary and secondary side of the inverter include harmonics, dif-
ferent meters indicate different measured values.
When installing meters etc. on the inverter output side
When the inverter-to-motor wiring length is large, especially in the 400 V class, large-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 recom-
mended to utilize the AM-5 terminal output function of the inverter.
When using measuring instruments for the normal frequency range, carry out the measurements as
described below.
NOTE For further information about measurements at the inverter refer to section 8.2.
I001313E
Fig. 7-7: Measurements at the main circuit
Input voltage
Input current
Output voltage
Output current
3-phase
power supply
Inverter
Instrument types
To the motor
Moving-iron type
Electro dynamometer type
Moving-coil type
Rectifier type