ABB NPBA-12, Installation And Startup Manual

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NPBA-12 Installation and Start-up Guide B-1
Appendix B – Definitions and Abbreviations
PROFIBUS Definitions
Acyclic Communication Communication in which messages are sent only once on request
Array Parameter consisting of data fields of equal data type
Broadcast Non-acknowledged message from master to all bus participants
(compare Multicast)
Command Word See Control Word
Communication Object Any object of a real device that can be communicated with (variable,
program, data range, etc.). Stored locally in the Object Dictionary
Control Word 16-bit word from master to slave with bit-coded control signals.
(Sometimes called the Command Word)
Cyclic Communication Communication in which Parameter-/Process Data-Objects are sent
cyclically at pre-defined intervals
Device Class Classification according to the number of profile functions included in
the device
Drivecast Broad- and Multicast, a special message frame for drives
Fault Event that leads to tripping of the device
GSD File ASCII-format device description file in a specified form. Each device
(active & passive stations) on PROFIBUS has to have its own GSD
File. GSD Files for various master stations are available from your local
ABB representative.
Index Access reference for Objects in PROFIBUS
Information Report Non-acknowledged message from master to one or all groups of bus
participants
Master Control system with bus initiative. In PROFIBUS terminology, master
stations are also called active stations
Multicast Non-acknowledged message from master to one group of bus
participants (compare Broadcast)
Name Symbolic name of a parameter
Nibble Set of 4 bits
Object Dictionary Local storage of all Communication Objects recognised by a device
Object List List of all accessible objects
Parameter Value that can be accessed as Object, e.g. variable, constant, signal