GE PACSystems RX7i, Руководство пользователя

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Chapter 4. Configuration
60 PACSystems* RX7i & RX3i TCP/IP Ethernet Communications User Manual GFK-2224Q
Ref Address The PLC memory reference address that contains the start of the data for this
variable.
Ignore Not used for Produced exchange.
Length Size of the data for this variable, expressed in units of the data type.
Type Data type of the variable.
Description
An optional text description of this variable.
To add a new variable to the end of the exchange, click the ‘
Add’ button. This does not change the data offsets
of any existing variables within that exchange.
To insert a new variable among the existing variables, click on an existing variable. When you click the ‘
Insert’
button, a new variable will be created
ahead
of the selected existing variable. This changes the data offsets of
all following variables in the exchange and will change the signature major number if you are using signatures.
Once a new variable has been entered, double-click a data field within the row to edit that value.
To delete an existing variable, click on the variable row and then click the ‘
Delete ’ button. If you are using
signatures, this will cause the signature major number to change.
The sum of the length for all variables in the exchange must not exceed 1400 bytes. The total length of the
exchange is displayed as ‘ Length (Bytes): ’ above the variable list. PACSystems CPUs with firmware version 5.0
and later support a maximum of 30,000 variables for all exchanges. Earlier firmware versions support
approximately 12,000 variables for all exchanges.
A variable is automatically created for the local exchange status that is returned to the PLC logic application.
The exchange status is not part of the produced exchange data and is not available to the network.
Configuring an Ethernet Global Data Exchange for a Consumer
To create a new consumed exchange, right-click the “Consumed Exchanges” node and select “New.” A dialog
box lists all produced exchanges in the EGD network that have been published to the EGD Configuration Server.
Select the exchange to be consumed. Once selected, the exchange is populated with the variable, length, type
and description information defined in the producer. The variable name consists of the target name, an
underscore, and the variable name in the producer. (See below for information about name generation.) You
must either enter a reference address or select “ignore” for each variable in the exchange. You must also
assign an adapter name and a timeout for the exchange. With these steps, the configuration of the consumer
is complete.
When an individual consumed exchange is selected, the following parameters can be configured in the
Properties Inspector window. Typically, only the adapter name and the update timeout need to be specified for
the exchange and the reference address specified for the variables in the exchange. Changing any other values
in a consumed exchange should only be done with expert help.
Name
A name assigned for this exchange. Defaults to the target name of the producer, an
underscore, and the exchange ID in the producer. Changing this name may make
resynchronization of the variable with the server impossible.
Producer ID The ID of the PLC producing the exchange. Producer ID is defined by the producer;
changing here it may make resynchronization with the server impossible.
Group ID Used only if the produced exchange has been configured with a Destination Type of
Multicast. Group ID is defined by the producer; changing it here may make it impossible to
consume the data from the producer.
Exchange ID Identifies a specific data exchange to be received by the consuming device. Exchange ID
is defined by the producer; changing it here may make resynchronization with the server
impossible.