This lets information from the safety system transfer into the plant-control system. The EtherNet/IP open-networking protocol extends standard, unmodified Ethernet TCP/IP using an open, industrially proven protocol at the application layer. Four distributed I/O (DIO) modules added to the GuardPLC line of safety controllers include an 8/8 digital input/output, a 16/8 digital input/output, an analog input/output, and relay output. The two digital I/O modules have bipolar outputs for use with robot controllers and other specialty output devices. The analog module has eight safety-rated inputs and four standard-analog outputs. The relay module has eight isolated relays that can switch power or provide a dry contact as an enable signal. EtherNet/IP can be implemented using only one wire for both safety and standard-network layers, simplifying the task of wiring the machine or cell.

Rockwell Automation, 1201 S. Second St., Milwaukee, WI 53204, (800) 223-5354,