How is the travel path measured?
The respective end switch is reached and switches a signal. This stops the positioning movement. Now, the drive direction is reversed and the positioning system drives slowly out of the end switch position. After a short distance, the end switch hysteresis, the end switch switches back to its default condition. This resetting of the end switch defines the respective limit of the travel path. This process is repeated with the opposite end switch. The distance between the limits is the length of the travel path.
The end of the travel path, the switch-point of the end switch and the position of the hard stop are generally different positions. Particularly with positioning systems that allow very high speeds, safe over-run paths must be maintained for braking the masses in the event of a fault. With positioning systems without end switches the travel path represents the path between the hard stops. It is not physically possible to drive the complete travel path with a constant speed. Depending on motorisation and target speed, acceleration and braking distances must be taken into account and these may lengthen the travel path required significantly.