The attribute expected package rate defines the maximum time between 2 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 on whether the connection is
producer or consumer.
4.2 I/O Assembly Instances
I/O assembly instances are several defined process control objects with defined content comprising control and status
information.
shows the I/O assembly instance options for controlling and monitoring the frequency converter.
Illustration 4.2 I/O Assembly Instance Options
4.3 Process Data
Process data comprises the control and status data in the I/O assembly instances.
The CTW, MRV, STW, and MAV have defined formats and functions, depending on the I/O instance selected. PCD 3 and PCD
4 are freely configurable, for instance 101/151 via
parameter 10-11 Process Data Config Write
and
.
All PCDs are freely configurable for instance 102/152.
DeviceNet provides a flexible way 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
parameter 10-10 Process Data Type Selection
.
This changes the I/O size to 4 words in the input and output area. This selection uses the Danfoss-specific profile for the
control word and status word as well as for the main reference value/main actual value.
The first 2 words are fixed on the DeviceNet, whereas PCD 3 and PCD 4 are user configurable. The number of PCDs active in
a system is fixed to 2 words.
NOTICE
To select
[1] Instance 101/151
in
parameter 10-10 Process Data Type Selection
, set
parameter 8-10 Control Word Profile
to
[0] FC profile
.
To enable use of PCD data from the DeviceNet, configure the contents of each single PCD word in
and
parameter 10-12 Process Data Config Read
. Changes to
parameter 10-11 Process Data Config Write
and
parameter 10-12 Process Data Config Read
are effected immediately in the PCD data.
Control
VLT
®
DeviceNet MCA 104
10
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MG92F102
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