Omron 1S Servo Motor Target Position Setting Out of Range

[sasi8hk]

Hi All.

I am setting up an Omron 1S Servo Motor to drive a conveyor. It goes forward 200mm, pauses and repeats until it is stopped.

However, after some time, the Servo goes into fault: Target Position Out of Range.

I believe that this is because the encoder count is close to the limit and the 200mm will send the count to overflow. I have used MoveRelative and MoveAbsolute functions. But the issue is still there.

Is there a way to reset the count? Or is there a proper function that does this? Thanks.

 

[Bobobodopalus]

It sounds like you want the servo in linear mode and not absolute, your problem may go away with the MoveLinear function

 

[sasi8hk]

Thanks Bobo. I will give it a try.

There are many move functions and I find the descriptions and the differences between the functions to be very vague.

 

[Peter Nachtwey]

How do you get a target position out of range error? Are there extend and retract limits?

Can you log exactly what the target position was when the error occurred?

Delta Motion and Rockwell have the concept of an "unwind" position which would be 200mm in your case. When the motor gets to 200 mm it automatically resets to 0 but not by resetting hardware counters.

These kinds of problems occur with rotatory applications too. Commands need to be able to indicate if moving positive, negative, nearest, absolute etc. as this affects which direction the target will move when going to the next position.