Switches & End Switches

The end of the travel, the switching point of the limit switch and reaching the hard stop are usually different positions. Particularly in the case of positioning systems that allow very high speeds, safe overrun paths must be provided for braking the masses in the event of an error.

Furthermore, it must be noted that the position of the activated and deactivated switch is different. This distance is called hysteresis.

When a system is switched on, a "homeing" or index run is usually necessary, during which the controller recognizes what the distance between the limit switches is and where the counter for the measuring system is to be set to 0.

The respective limit switch is approached and switches a signal, which the controller evaluates. Now the travel direction is reversed and the positioning system slowly moves out of the limit switch position. After a short travel, the limit switch hysteresis, the limit switch will clear and switch back to its normal state. This extinction of the limit switch defines the respective limit of the travel. This sequence is repeated with the opposite limit switch. The distance between the released limit switches is the length of the travel.

Cylindrical magnet (diameter 3 mm; height 1.5 mm) or cuboid magnet (10 x 4.5 x 1.5 mm)