The AZ 16 is to many companies the safety switch par excellence: the Schmersal Group already has produced many millions of this series and the switch is still highly popular. Schmersal now presents a new safety sensor, which will help many users make the step from electromechanical to non-contact guard door monitoring. Although the CSS 16 has the latest sensor technology inside, its basic size is exactly the same as that of the AZ 16 – with this particular difference that in the CSS devices the mechanical actuator is replaced by a compact target.

The CSS technology, which was developed and patented by Schmersal, enables a bidirectional communication between the sensor and the target and therefore offers distinctive advantages. The "Coded Safety Sensor" (CSS) principle provides for long switching distances. The sensors tolerate a misaligned actuation and emit a warning when the actuator is operating near the hysteresis range. In this way, the user is informed e.g. about guard door misalignments in an early stage, as a result of which he can timely readjust the door. In this way, the operating principle offers a high immunity to interference as well as high protection against tampering.

The CSS technology furthermore offers the advantage that a series-wired chain of up to 31 self-monitored devices (the number depends on the series used) can be set up, which meets the requirements of control category 4 or Performance Level e to EN 13849-1. The various connection variants and the comprehensive range of wiring accessories enable an elegant IP 67 connection to the machine without detriment to the safety level. The machine builder no longer needs an individual safety-monitoring module for each safety switchgear, which saves costs.

The CSS technology moreover makes additional information available, which can be used for diagnostic purposes for instance, thus increasing the availability of the machine. For the gathering, transfer and evaluation of the diagnostic-relevant signals, a new generation of gateways with interfaces for different field bus systems now is available.

All these advantages are now also available for existing machines, without the builder needing to change the mechanical construction: an AZ 16 can be smoothly replaced with a CSS 16. In this way, the machine builder can offer his customers the guard door monitoring feature with non-contact operating principle as an option and the machine users will quickly get acquainted with the additional possibilities of the non-contact position monitoring of guard doors.