Yaskawa AC Servo Motor SGMGH Series Static Check

Here at Precision Zone we offer refurbishing and reconditioning of Yaskawa SGMGH Sigma II series AC servo motors. In order to ensure where some issues stem from, we offer troubleshooting steps and procedures which can be performed on-site to help speed up the process of getting back up and running.
For these motors, one of the first tests to perform is a megaohm test using a megohmmeter. These meters are handy devices we recommend all shops to keep on hand for periodic checks to make sure motors are in proper running condition. When performing this test with the motor installed in the machine, the cables must be disconnected from the drive before using the megohmmeter. Failure to do so may result in heavy damage to the drive itself and further repair needed. These checks for motor insulation to verify the insulation is good and there are no ground faults.
Phase-to-phase resistance checks are also recommended to further verify the integrity of the motor. Standard multimeters can be used but milliohmmeters are recommended if available for use. These readings should be low, nearly short, and within 10% of one another.
If the motor is located outside of the machine, one other test that can be done is attempting to rotate the shaft by hand. If there is a brake on the motor, this will be held in place unless the brake is disengaged prior to rotating.
For further questions, comments, or concerns, feel free to contact us through phone at 800-551-4420 or visit us at www.precisionzone.net to request further assistance and we will be happy to assist you. We look forward to doing business with you.

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Question: is it possible to test servo motor insulation with insulation tester when Ac Tachogenerator is on it??