Mitsubishi Electric fr-e700 series, Instruction Manual, Page: 574 / 608

Measurements on the main circuit Maintenance and inspection
8 - 12
8.2.3 Measurement of voltages and currents
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.
I002040E
Fig. 8-10: Examples of measuring points and instruments
Input
voltage
Input
current
Output
voltage
Output
current
Power supply
Inverter
Instrument types
To the motor
Moving-iron type
Electrodynamometer type
Moving-coil type
Rectifier type
1-phase, 230 V
3-phase, 400 V
* At, As, Vt, Vs, W12, W13 are only for the three-phase power input
specification models.