Altech Non-Contact Safety Sensors

Product Announcement from Altech Corp.


The Altech SRF (Safety RFID) is a non-contact safety sensor that monitors movable  safety guards, such as doors, gates, panels and hoods. This compact sensor protects operators from injuries by shutting down or preventing the start up of machines when the safety guards are not properly closed.

Altech’s SMART
Non-contact Safety Sensor SRF

With an innovative diagnostic system

  • Very compact: small in size, flexible in use
  • Very Smart: suitable for Industry 4.0 with its intelligent diagnostic system
  • Cost Saving: four-wire unshielded standard connection cable from sensor to sensor
  • Very Safe: up to PL e – even in series connection with high defeat protection

Sensor and Actuator
The sensor and actuator feature a compact housing design which has a diagnostic LED and protection rating of IP69.  One actuator part number is used for all the coding types and is programmable without additional devices. The actuators are sold separately.   

M12 Connection in Series
The sensors are designed to be used in series and feature an M12 connection system which provides plug in installation convenience; saving time, wiring errors and labor.  Individual sensors are connected to a "main line" using a "T" connector.  The "main line" uses a four conductor unshielded cable, which offers additional cost savings.     

Safety Rating
The SRF offers a safety rating of up to PLe, Cat.4 / SIL CL 3 even when multiple switches are used in series, via redundant OSSD outputs.  

Diagnostics
There are two different levels of diagnostics available. PNP diagnostics offer a PNP NO output that indicates whether the safety guard is opened or closed.  DCD (Daisy Chain Diagnostics) offer much more detailed information providing over 20 different types of diagnostic information, via an internal bus system that can be accessed at the end of the series cable.  This data can be accessed by the machine’s control system via I/O Link and/or can be displayed on a Android Smartphone or tablet using NFC (Near Field Communication) technology.  Both levels of diagnostic systems operate independently of the safety outputs.

Fault Tolerant Outputs
The SRF also offers "Fault Tolerant Outputs", which prevent 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 indicated 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.

Local Reset Function
It is possible, with special versions, to install a button to reset the start function of the safety relay near the safety sensor using a "T" connector.  

Sensor / Actuator Coding
The sensors are offered with three different coding levels. Low Level Coded sensors are activated with any SRF actuator. High level coded sensors are pair 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 pairing procedure does not require any additional equipment.

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