ID 44001

FB error: axis reference changed, but former order isn't acknowledged.

Description

A job is to be sent via an FB to the motion controller. The commanded FB also sets the “Error” output to TRUE in the same PLC cycle and displays this error message at the “ErrorID” output since the FB instance already sent a job for another axis that is still active. Therefore, a different variable of type AXIS_REF was assigned to the “Axis” input and a rising edge was applied to the FB “Execute” input.

 

This is not permissible, otherwise the FB does not receive the job acknowledgement for the previously commanded axis and continues to be enabled.

Response

Class

-

The job is discarded by the FB and not transferred to the motion controller.

Solution

Class

-

In general there are 3 possibilities to respond to this error code:

  1. wait until the ongoing job is completed and then start the new job for the required axis.
  2. interrupt the ongoing job by an instance of MC_Halt or MC_Stop. When the axis is then in the state of FB error: axis reference changed, but former order isn't acknowledged., the job for the required axis can then be sent via the FB.
  3. the implementation is designed so that an axis is always assigned a definite FB instance. This means that changes do not occur at the “Axis” inputs of the FB.

Error type

-