CTI 2572-A, Инструкция по установке и эксплуатации

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CTI 2572-A Installation and Operation Guide V1.3 57
The following steps are required to configure the Control Logix system:
1. Define Control Logix tag names that you want to use to hold the data you will read from the 505
PLC and data you will write to the 505 PLC. For accessing multiple V memory locations, you
will need to dimension the tag as an array.
2. Create Message Blocks in your Control Logix program.
3. Configure each Message Block by selecting the following:
•
Message Type: CIP Data Table Read or CIP Data Table Write
•
Source Element: For a read operation, this is the 505 Tag Name. For a Write operation this is
the Control Logix Tag Name.
•
Number of Elements: Select the number of data elements to read or write
•
Destination Element: For a read operation, this is the Control Logix Tag Name. For a write
operation, this is the 505 Tag Name.
4. Specify the Communication options for each Message Block. This includes the path to the target
2572-A module.
Defining the Control Logix Data Tags
First, we will need to define some Control Logix tags. We will define two tags, one to hold the data
read from the 505 PLC and the other for the data we will write to the 505 PLC. Different formats are
used for the read and the write operations to illustrate the difference in accessing signed and unsigned
V memory data.
The tag named VMEMREAD will be used to store the data read from the 505 PLC. The tag data type
is defined as a 32 bit signed integer. This is done because we want to read unsigned integers from the
PLC, whose values may exceed the maximum that can be stored in a 16 bit signed integer (+32,767).
Note that the Control Logix processor does not support unsigned integer tags . This tag is
dimensioned to hold 100 values.
The tag named VMEMWRITE will be used to store the data that will be written to the 505 PLC.
Since we are writing signed 16 bit integers to the 505 PLC, this tag type is defined as a signed 16 bit
integer. This tag is dimensioned to hold 50 values.