Mitsubishi FR-E520-0.1K-NA Instruction Manual page 206

Note: 1. Use FFT to measure the output voltage accurately. It can not be measured
accurately with a meter or general instrumentation.
2. If the carrier frequency exceeds 5kHz, do not use this instrument since using it
may increase eddy-current loss produced in metal parts inside the instrument,
leading to burnout.
In this case, use an approximate effective value type instrument.
* The value within the parentheses is for the 400V class.
PROTECTIVE FUNCTIONS
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