Performing Layer Short
Testing of Motor Windings

Detect insulation failures (layer shorts) and deterioration in motor windings.
Generate pass/fail judgments with greater precision than conventional approaches by quantifying response waveforms.

Measurement Example

Capture Minuscule Variations That Do Not Appear in Response Waveforms

Detect minuscule defects that do not appear in response waveforms more effectively than conventional area comparison judgment (AREA, DIFF AREA) by quantifying response waveforms.

Since minuscule defects such as 1-turn shorts differ only slightly from the response waveform for a non-defective part, it's difficult to detect them using area comparison.

Carry Out Tests with The Rotor Installed

Changes in response waveforms caused by rotor position can also be quantified. Pass/fail judgments can then be generated by configuring non-defective and defective part areas.

Since the response waveform varies with rotor position in conventional area comparison judgment, it is not possible to make pass/fail judgments for the motor.

Equipment Used



・High-precision waveform detection: 200 MHz, 12-bit resolution

・Quantification of response waveforms
(using a patent held by Toenec Corporation)

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Discharge Detection Function ST9000

Discharge Detection FunctionST9000

・Detection of discharges obscured by noise

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