Sinamics V90: Motor started rotating at Full speed without giving any command.

Hello Everybody,

I am using V90 servo with S7-1200 CPU on TIA V16

This happening with us second time. 

When we changed following settings in the axis configuration of the TO

1. Selecting "Invert Encoder Direction"

2. Changing the Encoder type to "Linear Absolute"

We observed that after changing these parameters at different instances, 

And Enabling the drive in Commissioning mode of TO 

Motor started rotating at Full speed without giving any command. 

We restored this after resetting drive to factory default and also resetting TO object. 

Please suggest solution to this, as at first instance our mechanical system also got damaged. 

Thanks and Regards, 

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Split from Sinamics V90 Violent pos when power on..

Did you physically replace the encoder (or in some way rewire it) so the direction reversed as well as became a "linear absolute"?  Keep in mind, you did dot mention what type of encoder settings you had before changing the TO axis config in the S7-1200 project.

Rockon

Hello Everybody,

I am using V90 servo with S7-1200 CPU on TIA V16

This happening with us second time. 

When we changed following settings in the axis configuration of the TO

1. Selecting "Invert Encoder Direction"

2. Changing the Encoder type to "Linear Absolute"

We observed that after changing these parameters at different instances, 

And Enabling the drive in Commissioning mode of TO 

Motor started rotating at Full speed without giving any command. 

We restored this after resetting drive to factory default and also resetting TO object. 

Please suggest solution to this, as at first instance our mechanical system also got damaged. 

Thanks and Regards, 

Hello 0_Einstein,

Thanks for your reply, 

Neither we were replacing encoder, nor it changed automatically. 

In both cases, we were in commissioning stage, 

At first project, we just started, and we saw that we are getting -ve value of position as we move forward. So we changed that setting in TO, and downloaded the same to PLC, 

After finishing download, we activated axis in commissioning mode of the TO, and then pressed enable. As soon as we it got enables i.e. Servo ON state, it went to 2000RPM, and damaged mechanical system, and stopped with overload. 

Then we finished this project by multiplying actual position by -1.0, 

In second project, we were testing the motor and drive set in our factory, we were facing issue with homing position of the motor, 

The issue was after homing and power recycle it was showing >10000mm in actual position. So, we were going through forum, and we found a post mentioning these settings,

So, we changed Encoder type to the "Linear Absolute", After finishing download, we activated axis in commissioning mode of the TO, and then pressed enable. As soon as we it got enabled i.e., Servo ON state, started running at full speed, as motor was ideal in this case, it didn't damaged the system. 

After this incidence we factory reset drive from V-Assistance and Recalled TO object freshly in the PLC Project. 

Both projects have a gap of 6 months. 

It was horrible experience with V90,

I am using various Siemens Automation products since last 18 years, I have never imagined this would ever happen.

Thanks and Regards,