GE GFK-1541B manual Group Usage, Group ID IP Address

5

Group Usage

The group concept in Ethernet Global Data exchanges allows many EGD devices to simultaneously consume the same data produced by one producing EGD device. This capability is valuable for efficient bandwidth utilization in systems where data may be shared among multiple devices. This capability is made available by a technique called Multicasting. For more information on Multicasting, see the topic “Multicast IP Addresses” in the chapter: “Network Administration Support”.

Ethernet Global Data supports the use of 32 separate groups, each identified by a Group ID (1- 32). The EGD Group ID corresponds to a Multicast (Class D) IP address reserved by the Internet authorities (IP addresses 224.0.0.0 through 239.255.255.255). The default Multicast IP addresses used by EGD are:

Group ID	IP Address
1	224.0.7.1
2	224.0.7.2
.	.
.	.
.	.
32	224.0.7.32

These addresses are configurable within the Ethernet Interface using Station Manager, but are considered Advanced User Parameters and should only be changed if necessary to avoid a network conflict.

To enable group usage, configure the consumer exchanges to use the same Group ID (1-32) as the producer of the exchange.

In the PLC programming software:

1.In the producer definition, choose Group ID as the Destination Type. In the Consumer Address field, select a value between 1 and 32.

In the consumer definition(s), select the same value for Group ID that you entered in the producer definition’s Consumer Address field. The value 0 implies no group usage.

5-22 TCP/IP Ethernet Communications for the Series 90™ PLC User's Manual– May 2002 GFK-1541B