Many Factors Can Cause a Drive to Run Incorrectly11/22/2016The Magnetek AC drive just like many other brands has lots of circuitry built into the control to monitor all of its functions. One of the reasons that AC motor controls are used is the precise control they offer in the operation of AC motor current, torque, and speed. For our purposes here, we will address the speed control aspect of the AC drives. When a drive is set up by its programming to run at a given speed, today’s drives can calculate the speed of the motor even if it is an open loop setup. That is to say it can monitor the speed of the motor even without an encoder.There are many factors that can cause the motor to not run at the proper speed. If these factors are external, typically a change can be made to correct the situations, such as an adjustment to the motor load. Usually problems of this nature are the result of the motor not running fast enough. Sometimes the problem is that the motor is running too fast. This is an overspeed condition. The overspeed fault on the Magnetek AC drives built by Yaskawa are indicated by an OS fault on the digital operator or keypad. Some of the series that fall into this category are the GPD 503 drives, GPD 505 drives, GPD 506 drives, GPD 515 drives, GPD 315 drives, GPD 333 drives and others manufactured during the Magnetek / Yaskawa association. The description of the overspeed fault condition from a Magnetek operator manual: The motor speed feedback exceeded the value set for a time longer than the setting.What happens to cause a motor overspeed fault on an AC drive? A few causes may be that the acceleration time is set too fast and causes the motor to overshoot the target speed. A sudden change in the load may also cause the drive to indicate an over speed condition. These issues will most likely cause nuisance faults, but are easily corrected in the field by an operator or technician. Another possibly not so easily correctable cause for an overspeed fault or alarm is the loss of the drive’s speed reference. Without the speed reference to tell the drive how fast to run the motor or the feedback that tells the drive how fast the motor is running.If the over speed fault cannot be cleared by an adjustment to the load or a change in the programming, it may be time to start thinking about repair. Especially if it is constantly happening while the drive is in the process of running the motor. The decision on whether drive repair is needed gets really tricky when there is an intermittent overspeed failure. It’s usually an indication that something within the drive is right on the verge of a permanent failure.Once you determine that a repair is indeed needed, call on the Magnetek AC drive repair experts at Precision Electronic Services, Inc. at 800-732-4695, to get your drive sent in to us for a free evaluation and repair price quotation. Back To Blog
Many Factors Can Cause a Drive to Run Incorrectly11/22/2016The Magnetek AC drive just like many other brands has lots of circuitry built into the control to monitor all of its functions. One of the reasons that AC motor controls are used is the precise control they offer in the operation of AC motor current, torque, and speed. For our purposes here, we will address the speed control aspect of the AC drives. When a drive is set up by its programming to run at a given speed, today’s drives can calculate the speed of the motor even if it is an open loop setup. That is to say it can monitor the speed of the motor even without an encoder.There are many factors that can cause the motor to not run at the proper speed. If these factors are external, typically a change can be made to correct the situations, such as an adjustment to the motor load. Usually problems of this nature are the result of the motor not running fast enough. Sometimes the problem is that the motor is running too fast. This is an overspeed condition. The overspeed fault on the Magnetek AC drives built by Yaskawa are indicated by an OS fault on the digital operator or keypad. Some of the series that fall into this category are the GPD 503 drives, GPD 505 drives, GPD 506 drives, GPD 515 drives, GPD 315 drives, GPD 333 drives and others manufactured during the Magnetek / Yaskawa association. The description of the overspeed fault condition from a Magnetek operator manual: The motor speed feedback exceeded the value set for a time longer than the setting.What happens to cause a motor overspeed fault on an AC drive? A few causes may be that the acceleration time is set too fast and causes the motor to overshoot the target speed. A sudden change in the load may also cause the drive to indicate an over speed condition. These issues will most likely cause nuisance faults, but are easily corrected in the field by an operator or technician. Another possibly not so easily correctable cause for an overspeed fault or alarm is the loss of the drive’s speed reference. Without the speed reference to tell the drive how fast to run the motor or the feedback that tells the drive how fast the motor is running.If the over speed fault cannot be cleared by an adjustment to the load or a change in the programming, it may be time to start thinking about repair. Especially if it is constantly happening while the drive is in the process of running the motor. The decision on whether drive repair is needed gets really tricky when there is an intermittent overspeed failure. It’s usually an indication that something within the drive is right on the verge of a permanent failure.Once you determine that a repair is indeed needed, call on the Magnetek AC drive repair experts at Precision Electronic Services, Inc. at 800-732-4695, to get your drive sent in to us for a free evaluation and repair price quotation.