A compact, coded non-contact guard-door monitoring sensor is seen as an alternative to electro-mechanical safety switches for monitoring the position of the safety guards.

Man-machine safety specialist Schmersal has introduced the BNS 260, a compact, coded non-contact guard-door monitoring sensor, which the company sees as an alternative to electro-mechanical safety switches for monitoring the position of the safety guards. Features include its compact size and the coded NC contact that guarantees a high level of safety, which, when used with an appropriate safety-monitoring module such as Schmersal's AES series, meets the requirements of Control Category 4 to EN 954-1 or SIL Level 3 to IEC 61508. It is also suitable for applications of PDF class M to EN 60204-1.

Users can also choose between 1 NO / 1 NC and 2 NC contacts and the signalling contact can be NO or NC.

The BNS 260 also features an optional LED, which signals the switching condition, and for applications where the sensor must be fitted in a 90deg rotated position, a special actuator version with lateral active surface is available.

Commenting for Schmersal, managing director Terry Hayward said: 'The BNS 260 is extremely compact and can be easily integrated into a machine's construction.

By using the non-contact operating principle, it is not subject to mechanical wear and therefore has an extremely long life, making it ideal for use in harsh ambient conditions as well as where high hygienic standards have to be maintained.' The BNS 260's switching distance matches the needs of typical applications during the position monitoring of guard doors and, thanks to it non-contact design, can tolerate much larger misalignment between the machine profile and the safety guard.