Tamper-proof safety transponder with RFID technology

SICK’s UK Safety Specialist and FS Engineer, Dr Martin Kidman, explained: “Two big challenges with non-contact safety switches on removable guards are the mounting requirements and their susceptibility to tampering.”

Kidman continued: “Large door offset tolerances and high levels of shock and vibration cause reliability issues. Additionally, the temptation for operators to defeat the guard because of piece-working or a lack of special modes of operation, for example, makes manipulation a huge problem.”

To allow for flexibility during mounting, the STR1 has three different actuators, each of which can be actuated from four different mounting directions. With its compact VISTAL housing, the STR1 offers mechanical stability, high EMC immunity and an IP67 enclosure, to ensure excellent reliability in harsh environments.

“The SICK STR1 is highly resistant to tampering whether through accidental damage or deliberate attempts to manipulate or ‘defeat’ a switch for operational convenience, by offering a choice of universal, unique or permanent coding options and unidirectional mounting screws. So high levels of machine availability are ensured,” added Kidman.

The STR1 continually self-monitors its semiconductor Output Safety Switching Devices (OSSDs) to detect failures and has LED status indicators for fast diagnostics. Three coding types are available: universally-, unique-, and individually -coded.

For applications that are susceptible to manipulation, uniquely- and permanently-coded variants can be used dependant on the risk. With high levels of resistance to manipulation, the requirements of EN ISO 14119 can be fulfilled.

The versatility of the SICK STR1 Transponder Safety Switch makes it easy to integrate. As it can be applied almost universally, it can reduce stocks of safety switches to a minimum.