GE Industrial Solutions AF-650 GP DeviceNet - Manual (Page 17)

The Attribute Expected Package Rate defines the maximum time between two COS messages even when the value is unchanged. In the event of COS connection,
the Explicit Package Rate is identical with the Heartbeat Interval mentioned above. This timer is used both as transmission trigger and inactivity watchdog,
depending upon whether the connection is producer or consumer.
4.2 I/O Assembly Instances
I/O Assembly Instances are a number of defined process control objects with defined content comprising control and status information. The figure below shows
the I/O Assembly Instance options for controlling and monitoring the frequency converter.
4.3 Process Data
Process data comprises the control and status data in the I/O Assembly Instances.
The CTW, MRV and STW and MAV have defined formats and functions, depending upon the I/O Instance chosen. PCD3 and PCD4 are freely configurable for
instance 101/151 via par. DN-11 Process Data Config Write and par. DN-12 Process Data Config Read.
All PCDs are freely configurable for instance 102/152
DeviceNet provides a flexible way for the user to customize the number of Process Data (I/O words) and the functionality of each word. To activate the user
definable process data, select the I/O Instance 101/151 in par. DN-10 Process Data Type Selection. This will change the I/O size to four words in the input and
output area. This selection uses the GE-specific profile for the Control word and Status word as well for the Main Reference Value/Main Actual Value.
The first two words are fixed on the DeviceNet, whereas the user can select the input and output, PCD 3 and PCD 4. The number of PCDs active in a system is fixed
to 2 words.
NB!
Selection of Instance 101/151 under par. DN-10 Process Data Type Selection is only possible if GE Drive Profile has been selected in par. O-10 Control Word
Profile.
To enable use of PCD data from the DeviceNet, configure the contents of each single PCD word in par. DN-11 Process Data Config Write and par. DN-12 Process
Data Config Read. Changes to par. DN-11 Process Data Config Write and par. DN-12 Process Data Config Read are effected immediately in the PCD data.
AF-600FP /650 GP DeviceNet Operating Instructions
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