User manual

96 Publication ENET-UM001I-EN-P - January 2010
Chapter 7 Interlocking and Data Transfer Between Controllers
Connections for Produced
and Consumed Tags
Logix controllers can produce (broadcast) and consume (receive)
system-shared tags that are sent and received via the EtherNet/IP
communication module. Produced and consumed tags each require
connections.
All EtherNet/IP modules support as many as 32 produced multicast
connec
tions
. Because each tag that passes through an EtherNet/IP module
uses a single connection, the number of available connections limits the total
number of tags that can be produced or consumed. If the communication
module uses all of its connections for I/O and other communication modules,
no connections remain for produced and consumed tags.
Required Connections for Produced and Consumed Tags
Tag Type Required Connections
Produced The local controller (producing) must have one connection for the produced tag and the first c
onsumer and one more
connection for each additional consumer (heartbeat). The produced tag requires two connections.
As you increase the number of controllers that can consume a produced tag, you also reduce the number of c
onnections the
controller has available for other operations, such as communication and I/O.
Consumed Each consumed tag requires one connection for the controller that is consuming the tag.
IMPORTANT
Depending on whether it is producing or consuming a tag, a
Logix5000 controller uses its connections differently.
Number Connections for Produced and Consumed Tags
Type of Tag Device Number of Connections Used
Produced tag Logix5000 controller Number_of_consumers + 1
EtherNet/IP module 1
Consumed tag Logix5000 controller
EtherNet/IP module
1