On-Line Motor Insulation Testing

Motor Protection for "High Value" Process / Motor Applications

• Do you care about the winding insulation status of your motors?
• Would it be beneficial to have a “real-time” winding insulation monitor to continuously check the status of your motor or generator windings?
• Do you perform preventative maintenance on motors or generators?
• Are you concerned with ARC Flash requirements, related to motor maintenance?

If you answered yes to any of the above, Meg-Alert has the products you seek! Meg-Alert manufactures the MotorGuard and GenGuard patented testing and protection systems designed to detect insulation breakdown in critical motors and generators. The system senses when the motor or generator is offline and then performs a continuous dielectric test on the winding insulation until the equipment is started again. When an abnormal condition is detected, the equipment can be locked out and a warning signal sent, indicating that the motor or generator needs maintenance. The testing is done with a current limited non-destructive DC voltage from 500 - 5000 VDC, which is safe for both personnel and the equipment. By automatically testing offline equipment, customers can now predict and prevent impending failures, reduce unscheduled downtime repairs, and increase plant safety by not exposing maintenance personnel to dangerous Arc Flash conditions experienced when performing manual testing.

Automation makes it practical and affordable to keep your motors in proper running condition. The use of the Meg-Alert products can dramatically increase plant productivity by reducing downtime and improving safety conditions if done correctly. The windings are the key indicators of degradation and potential failure. If you have a properly mounted, balanced, grounded, and lubricated motor, you can probably rule out bearing failure, leaving the windings as the weak link. So, insulation resistance testing can give you a real key in predicting motor failure.  There is little doubt that insulation testing is valuable, but using them can be difficult and time consuming. If you utilize "Automatic offline insulation testing", it can provide you with real-time winding conditions before starting, which is the most intense part of motor operation, and the point when a motor is most likely to fail. When the motor stops operating, the Meg-Alert device applies a test voltage signal to the windings and measures any leakage current to ground.  The device, usually coupled to a meg-ohm meter or analog signal device will alert you when the insulation resistance drops below an acceptable level. The Meg-Alert device can lockout the motor controller to disable the motor starting, thus preventing the motor from starting and causing a failure.  After you correct the winding insulation problems, you can reset the system and return the motor to normal operation. In addition, Standard Electric Supply Co can assist you in getting your motor status by e-mail, SMS message or other notifications.

Please read this article by Rick Zelm, President of Meg-Alert, Inc.: PEM Magazine

Also, check out Meg-Alert's web site for more information: www.megalert.com or visit our web site www.standardelectricsupply.com