# Overview

## Task

To monitor position lag, check the difference between the command position and the actual position value of a CNC axis.

If a configurable limit is exceeded, the CNC generates an error message and the axis is stopped.

## Characteristics

The position lag monitor checks the correct functioning of the position controller.

For example, it can detect the following problems:

- Dynamic axis overload due to excessive velocity or acceleration settings
- Mechanical changes to axes, e.g. increased friction due to damaged bearings or guides
- Errors in the axis position measuring systems

## Parameterisation

The position lag monitor is configured for each individual axis in the axis parameter list.