User Manual Owner's manual

Rockwell Automation Publication 440R-UM009B-EN-P - February 2014 11
About the Interface Chapter 1
Specify the Requested Packet
Interval (RPI)
The Requested Packet Interval or RPI is the update rate specified for a particular
piece of data on the network. The RPI can be specified for the interface and
include all of the Guardmaster Safety Relays in the system.
When you add an interface to the I/O configuration of a controller, you must
enter the RPI as a parameter. This value specifies how often to produce the data
for that device. For example, if you specify an RPI of 50 ms, it means that every
50 ms the device should send its data to the controller and the controller should
send the consumed (output) data to the device.
Use RPIs only for devices that exchange data. For example, a ControlLogix
EtherNet/IP bridge module in the same chassis as the controller does not require
an RPI, because it is not a data-producing member of the system. Its use is only as
a bridge to remote racks.
Support of Data Connections
TheGuardmaster EtherNet/IP Network Interface supports data connections.
A data connection to the interface is a grouping of data from one or more
Guardmaster Safety Relays into a single block of data sent over a single
connection at the same data rate.
See the EtherNet/IP Design Considerations Reference Manual,
publicationENET-RM002
for more information on connections.
Chapter Summary
In this chapter, you were introduced to the features of the Guardmaster
EtherNet/IP Network Interface, and considerations for installation and usage.