Position and limit switches

Limit switches and position switches detect motion sequences

In mechanical engineering, sequence controls that consist of several work steps are often used. In this case, the position switches register the end of a movement and trigger the start of the next step.

For example, the switches are also used in roller doors for underground car parks: a limit switch detects when the door has reached its end position, i.e. when it is fully raised. The electric drive is then stopped and the traffic light in front of the door changes to green.

Various series from Schmersal

The Schmersal Group's range includes various series of limit switches. These range from ultra-compact position switches for integration into automated systems to microswitches and extremely robust switching devices. The latter are primarily used in adverse environmental conditions, such as those found in conveyor technology or the steel industry. All limit switches are equipped with NC or NO contacts in accordance with IEC 60947-5-1. In conjunction with a suitable safety evaluation, a single switch can achieve up to Performance Level d (PL d) according to EN ISO 13849-1.

Switches with AS-i-SaW interface

Part of the Schmersal Group's position switch programme has an integrated AS-i-SaW interface (AS-Interface Safety at Work). These utilise the advantages of the simple and proven bus system, which is based on the open standard AS-International. The ATEX/IECEx certified versions are also suitable for use in potentially explosive atmospheres. Schmersal offers solutions for zones 2 and 22 as well as 1 and 21 in this area.
 

Versatile limit switch and position switch versions

Some limit switch and position switch series can be used at ambient temperatures between -40 and +80 °C. Various different switch bodies are available, as are metal or plastic versions. Actuators to EN 50041 and EN 50047, as well as mounting dimensions and switch points, allow universal use. Accordingly, the switches can also be retrofitted or installed in existing machine designs.

Actuators for limit switches and position switches

As a supplement to the available limit switches and position switches, Schmersal offers a range of actuating elements such as plungers, roller levers, angled levers or rod levers. The user can choose between switching elements with up to three contacts. The Schmersal Group provides detailed information on the individual components in its extensive online catalogue.