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AKD F465 Excessive Shock Detected By Feedback Device ( Hiperface DSL )
From Workbench Help
We've only seen this in one instance so far but here are more details on what we know about this fault.
The Hiperface DSL encoder has an internal accelerometer and creates a fault when the encoder has, what the encoder thinks, is excessive vibration. The encoder doesn’t care the source of vibration or if the motor is enabled or not. We have no control over its setting or a way to disable it. The feedback manufacturer put the accelerometer in the encoder for a reason so the remedy is to locate sources of the vibration and suppress them.
In the instance we experienced, the load was vertical and when the motor stopped ( and then the brake engaged ) the load would shudder and the fault would occur. The reason for the abruptness was a controlled stop was not being used therefore the brake timing was not being used and the intrinsic engage time of the mechanical brake on the motor was enough time to allow the load to fall for that time before the brake engaged. By using a controlled stop the timing was used and the load was held until the brake could be applied using the brake time in the drive.
I encourage you to read the following KDN article as it explains controlled stop and holding brake timing in the AKD drive.