Eliminated from:
PLC Designer V3.6
SM3_DriveLenze library V3.6
Behaviour of the new version:
Operation without following error is possible after executing the SMC3_ReInitDrive FB. The speed feedforward control value is scaled correctly.
Which products are concerned?
PLC Designer V3.5 or higher
SM3_DriveLenze library V3.5 or higher
What happens?
The Motion axis of the i700 servo inverter follows the controller setpoints with a following error.
When does the problem occur?
Operation without following error is only possible if the speed feedforward control value is transmitted with the correct scaling from the controller to the drive.
The scaling is recalculated in the SMC3_ReInitDrive function block contained in the SM3_Basic library.
If the transmission ratio was set using the SMC_ChangeGearingRation function block of the same library, a subsequent call of the SMC3_ReInitDrive FB will lead to a change of the transmission ratio and, accordingly, in the case of motion, to a following error.
Possible diagnostics:
At constant speed, there will be a constant deviation between setpoint and actual position (following error).
Short-term measures/recommendations:
Call the L_SMC_FactorVel function block after calling the SMC_ReInitDrive FB.
You can find the function block attached to this AKB article. Please proceed as follows to integrate the FB into your PLC project:
- Copy the L_SMC_FactorVel.ZIP file to your PC.
- Unpack the file.
- Start PLC Designer V3.x and open your PLC project.
- Go to the device tree, select the element "Application" and execute the menu command Project>Import PLCopenXML... .
- Select the L_SMC_FactorVel entry in the "Import PLCopenXML" dialog and click <OK>.
Now, the function block is available in your project.
Evaluation:
The SMC3_ReInitDrive FB is used to reinitialise a Motion axis and must be called to activate the settings selected with the SMC_ChangeGearingRatio FB. Calling SMC3_ReInitDrive will, however, change the settings selected with the SMC_ChangeGearingRatio FB. This may lead to a deviation between setpoint and actual position. As a workaround for this function restriction, you can call the L_SMC_FactorVel function block attached to this AKB article.
