ABB RETA-02, User Manual

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Communication profiles
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The ABB Drives communication profile
The Control Word and the 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 on the Control
Word, and returns status information to the master in the Status
Word.
The contents of the Control Word and the Status Word are
detailed in
Table 7. and Table 8. respectively. The drive states are
presented in the ABB Drives profile state machine ( Figure 12. ).
References
References are 16-bit words containing a sign bit and a 15-bit
integer. A negative reference (indicating reversed direction of
rotation) is formed by calculating the two’s complement from the
corresponding positive reference.
ABB drives can receive control information from multiple sources
including analogue and digital inputs, the drive control panel and a
communication module (e.g. RETA-02). In order to have the drive
controlled through the fieldbus, the module must be defined as the
source for control information, e.g. Reference.