Non-contact safety switch
August 1st 2005 Available from Pilz Automation Technology, the PSENcode series of coded non-contact safety switches are for applications conforming to the requirements of EN 954-1 category 4 that need a high level of guard switch integrity.
Three types of switches are available, with the special coded version having a matched switch and actuator that will only work in combination with each other.
The company says the switches are virtually impossible to defeat and that cost advantages can be gained on machinery fitted with multiple opening guards. Whereas a Category 4 application would normally require two mechanical switches per guard (to ensure mechanical redundancy), each connected to a separate channel on a safety relay (for electrical redundancy), 10 or more PSENcode switches can be connected in series, all monitored by a single relay.This leads to savings in hardware costs. More articles from Pilz Automation Technology: | 
