NEMA, the National Electrical Manufacturers Association, has released two new annexes to supersede annexes B and E in ICS 5-2000, Industrial Control and Systems: Control Circuit and Pilot Devices. ICS 5 provides general requirements for control circuit and pilot devices used in industrial applications for control-circuit switching and the control of solenoids. It covers the requirements for control relays, limit switches, proximity switches, pushbuttons, selector switches, indicating, and pushbutton stations.
ICS 5, Annex B-2002, Typical Proximity Switch Specifications, contains specifications that represent common dimensions and operating characteristics for proximity switches. It focuses only on inductive cylindrical proximity switches with threaded barrel, type I-A. “Annex B now offers customers the ability to quickly compare inductive proximity switches, marketed as ‘extended range,’ since the publication defines the extended range specification commonly used with these types of proximity devices,” said Gil Guajardo, chair of NEMA’s Industrial Proximity and Presence Sensors task force.
ICS 5, Annex E-2002, Additional Requirements for Proximity Switches Suitable for Use in Strong Magnetic Fields, gives performance and test conditions for proximity switches such as electric weld fields (normally alternating) or electrolytic fields (normally constant). "This new annex will allow users of these types of devices the ability to quickly select the proper proximity switch appropriate for the environment,” said Guajardo.
The two annexes may be purchased for $36.00 each by contacting Global Engineering Documents at (800) 854-7179 (within the U.S.), (303) 397-7956 (international), (303) 397-2740 (fax), or on the Internet at www.global.ihs.com. They may be viewed on the Internet by visiting www.nema.org/industrialcontrols/ and clicking on “Standards & Other Publications” in the right column.