During a workshop assessment, the reported condition is: A variable-frequency drive output is being checked with a basic average-responding meter, and the reading appears unstable. What tool choice is more appropriate?
Answers
Ameasure only protective-earth resistance
Bassume the displayed average is always the motor RMS voltage
Cuse a meter and method rated for the drive waveform and required true-RMS bandwidth
Duse an uninsulated analog probe
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