Wake and Shake Overview

Motors which have no way to automatically identify commutation must run Wake and Shake. Motors without Halls fall into this category, as well as motors whose hall effect sensors were manually installed, and not aligned to a motor phase of 0 degrees.

The AKD will determine if Wake and Shake is needed for safe operation based on feedback type. If needed, the drive will automatically arm Wake and Shake. If Wake and Shake does not complete, a fault will be generated. When that fault is cleared, Wake and Shake will be automatically armed again.


  • If the user attempts to manually disarm Wake and Shake on an AKD which requires it, a fault will be thrown and Wake and Shake will automatically arm again.

If Wake and Shake is armed on a motor with a feedback type that does not normally require Wake and Shake, the algorithm will still execute. If Wake and Shake fails, a fault will be generated. After the faults are cleared, Wake and Shake will automatically arm again.


  • If Wake and Shake has been manually armed, it can be disarmed by clicking on the "disarm" button on the Wake and Shake screen, or by executing the WS.DISARM command over telnet.

The AKD has multiple modes of completing Wake and Shake, each with different benefits for different operating conditions.

Mode 0:

Mode 0 is the fastest of the Wake and Shake methods; it executes and completes in a few seconds, and is ideal for applications that need the fastest start-up time. The tradeoff for this fast execution time is complexity in configuration. There are a lot of parameters that must be precisely tuned for this mode to operate correctly.

For more information see Using Wake and Shake Mode 0 (WS.MODE 0) (pg 1)

Mode 1:

Mode 1 is a more traditional method of completing Wake and Shake. It is also referred to as Commutation Alignment and Pole Locking. Mode 1 takes a little longer to execute than Mode 0, but is easier to configure. Only WS.IMAX (current to be applied) and WS.TSTANDSTILL (time to apply current) need to be configured. The default values work for most motors.

For more information see Using Wake and Shake Mode 1 (WS.MODE 1) (pg 1)

Mode 2:

Mode 2 is the easiest of the Wake and Shake modes. It requires no parameters to be configured (setting WS.FREQ for sine frequency excitation is optional, and the default value of 10,000 Hz will work for most cases). This Auto-Commutation finding algorithm can take as long as 30 seconds to complete. Measurements are taken by exciting the motor with a sine excitation as the motor phase is adjusted. After a series of data points have been taken a DFT analysis is done to determine the motor phase offset for commutation.