The new SMART Non-Contact Safety Sensor SRF from Altech Corp. protects machine operators from potential injury by monitoring moveable separating protective devices (such as doors, gates, panels, and hoods) and shutting down or preventing startup of a machine when a device is not properly closed. The SRF sensor is also the only safety sensor currently on the market integrating an intelligent diagnostic system, which collects data for early detection of machine faults and allows for timely maintenance fixes. Sensors are available with diagnostics function that can be monitored with I/O Link supporting Industry 4.0 implementation and Smart Factory operations.
SRF (Safety RFID) sensors are compact (36.5 x 26.2 x 15 mm) and will suit any application where safety switches (Type 2) or sensors (Type 4) would be used, including machines for packaging, turning and milling, food processing, woodworking, and injection molding, among many others.
Data for up to 20 different switch conditions can be monitored for each individual sensor, even when they are connected in a series for monitoring multiple access points. Critical data is stored in the sensor with a time stamp and can be reviewed even in the event of a power failure. The collected data can be viewed on a computer via I/O link or displayed on smartphones via NFC technology. Two levels of diagnostics (basic PNP and extended Daisy Chain Diagnostics) are available.
Up to 32 SRF sensors can be safely connected in series using standard four-wire unshielded cables with M12 connectors, which promotes plug-and-play installation convenience. A single cable linking sensor to sensor eliminates unwieldy wire bundles and typical accessory costs.
The sensors are offered with three different coding levels. Low level coded sensors are activated with any SRF actuator. High level coded sensors are paired with one specific actuator. Unique level coded sensors can only be paired once. After pairing, the sensor cannot be activated with any other actuator.
The SRF sensors also offer “Fault Tolerant Outputs,” which prevents unnecessary machine shutdowns. If both OSSD safety outputs are lost, caused by an unsafe condition (such as a door being opened), the machine will immediately shut down. However, if only one output is lost (caused by a fault in the sensor or wiring), the sensor will indicate the condition with a flashing code and transmit the information via the DCD system (if used). After 20 minutes the machine will be shut down.
SRF sensors possess the highest safety ratings (PLe, Cat. 4 according to EN ISO 13849-1 and SIL CL3 according to DIN EN 62061) and are in compliance with ISO 14119. The system’s transmitter, receiver, connectors, and wiring are IP69-rated to withstand harsh processes, including wash-downs.
Unlike traditional keyed switch or reed switch technologies, SRF sensors are especially rugged and immune to vibration, Solid-state components perform wear-free during the system’s expected service life rating up to 20 years. Custom versions can be developed to meet specific application requirements or demands.
Filed Under: Sensor Tips