Rockwell Automation PowerFlex 750-Series, Руководство пользователя

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Configuring the I/O 4-11
PowerFlex 750-Series Drive DeviceNet Option Module User Manual
Publication 750COM-UM002A-EN-P
Figure 4.15 Edit I/O Parameters Screen
A. Select the type(s) of data exchange (Polled, Change of State,
and/or Cyclic). For this example, we selected Polled, which is
highly recommended.
B. Enter the number of bytes that are required for your I/O in the
Input Size and Output Size boxes. For the example in this
manual, all 16 [DL From Net xx] and all 16 [DL To Net xx]
are used, resulting in an Input Size of “72” and an Output Size
of “72.” To determine the byte sizes for your application, either
access Option Module Diagnostic Items 7 and 8 respectively or
calculate them:
Determining Byte Sizes By Accessing Diagnostic Items 7 and 8
Use the HIM, DriveExplorer or DriveExecutive to access
Diagnostic Items 7 and 8. The Option Module automatically
calculates the number of bytes for the Input Size and Output
Size based on the values of Device Parameters 2 - [DLs From
Net Cfg] and 4 - [DLs To Net Cfg] configured in
Setting a
Master-Slave Hierarchy (Optional) on page 3-3 .
Determining Byte Sizes By Calculation
You can easily calculate the number of bytes for the Input Size
and Output Size. Since the Option Module always uses the
32-bit Logic Command, 32-bit Feedback, 32-bit Logic Status,
and 32-bit Reference, at least 8 bytes must be set for both the
Input Size and Output Size. (A 32-bit word is four bytes.) If any
or all of the drive’s sixteen 32-bit Datalinks are used (see
Setting a Master-Slave Hierarchy (Optional) on page 3-3 ),
increase the Input and Output Size settings accordingly. To do
this:
– Input Size: Multiply the number of Datalinks used to write data
(value of Device Parameter 02 - [DLs From Net Cfg]) by 4
bytes, and add this result to the minimum 8 bytes. For example,
if Parameter 02 has a value of “3,” add 12 bytes (3 x 4 bytes)
to the required minimum 8 bytes for a total of 20 bytes.