Control Word And Status Word - ABB ACS880 Firmware Manual

634 Fieldbus control through a fieldbus adapter
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Control word and Status word

The Control word is the principal means for controlling the drive from a fieldbus
system. It is sent by the fieldbus master station to the drive through the adapter
module. The drive switches between its states according to the bit-coded instructions
in the Control word, and returns status information to the master in the Status word.
For the ABB Drives communication profile, the contents of the Control word and the
Status word are detailed on pages 637 and 638 respectively. The drive states are
presented in the state diagram (page 639).
When a transparent communication profile is selected e.g. by parameter group 51
FBA A settings, the control word received from the PLC is available in 06.03 FBA A
transparent control word. The individual bits of the word can then be used for drive
control through bit pointer parameters. The source of the status word, for example
06.50 User status word 1, can be selected by 50.09 FBA A SW transparent source.
Debugging the network words
If parameter 50.12 FBA A debug mode is set to Fast, the Control word received from
the fieldbus is shown by parameter 50.13 FBA A control word, and the Status word
transmitted to the fieldbus network by 50.16 FBA A status word. This "raw" data is
very useful to determine if the fieldbus master is transmitting the correct data before
handing control to the fieldbus network.