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This PowerPoint presentation explains the differences between different types of servo motor feedback devices, including:

  • The differences between absolute and incremental devices.
  • The differences between analog and digital devices.
  • Typical applications for various devices.
  • How to choose the best feedback device for your specific application.
  • How the devices affect servo system performance.

Commutation is the means by which a servo drive controls the torque of a motor by determining the position of the motor and applying current to the appropriate motor phases.  If the rotor position of the motor is not determined correctly or the motor power phase wires are wired to the wrong terminals, the drive will apply current to the wrong phase at the wrong time (or at the wrong rotor position).  This will cause the motor to run away or lock up.

First to review what F402 means:

Analog signal amplitude for resolver or sine encoder feedback is out of range, either too low or too high.

To troubleshoot:

Check primary feedback (X10 connection), for resolver and sine/cos encoder only.

When I use frameless DD motor with Resolver, can AKD adjust phase between motor and resolver?

Or, do I need to adjust it physically during hardware installation? 

The setting for FB1.ENCRES (Rotary Encoder Resolution) for a resolver is set automatically in Workbench to a value of 32768 * FB1.POLES.  So it is set to 65536 for a 2-pole resolver or 131072 for a 4-pole resolver.  A resolver does not have encoder pulses or an encoder line count or resolution.  But the drive sets this parameter in order to handle the required interpolation and resolution of the resolver signals.  Basically, you can ignore this parameter when using a resolver.

Add resolver frequency to AKD User Guide

In the next revision of the AKD User Guide (P/N 903-200006-00), add the following note at the end of section Resolver (p.76):

(link to AKD User Guide:

(Only the information between the horizontal lines is to be added to User Guide.)

Attached file ( AKD with PacSci R22G data.xlsx)   with Cut and Paste that the did not copy below

Trying to get a  PacSci R22G with resolver – no accurate documentation for the resolver connection since it is a custom (-03 at end of part# and build was in 1989)– so trying to guess in a methodical way.

I did a continuity check across (3) windings of the resolver – see below:

Valid for S300, S400, S600, S700