VACON CX
Profibus user’s manual
Page
6
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Vacon Oyj
Phone +358-201-2121
Fax: +358-201-212 205
3. PROFIBUS
DP
3.1 General
PROFIBUS is a vendor-independent, open fieldbus standard for a wide range of applications in
manufacturing, process and building automation. Vendor independence and openness are guaranteed
by the PROFIBUS standard EN 50 170. With PROFIBUS, devices of different manufacturers can
communicate without special interface adjustments. PROFIBUS can be used for both high-speed time
critical data transmission and extensive complex communication tasks. The PROFIBUS family consists
of three compatible versions.
PROFIBUS-DP
Optimized for high speed and inexpensive hookup, this PROFIBUS version is designed
especially for communication between automation control systems and distributed I/O at the
device level. PROFIBUS-DP can be used to replace parallel signal transmission with 24 V or 0
to 20 mA.
PROFIBUS-PA
PROFIBUS-PA is designed especially for process automation. It permits sensors and actuators
to be connected on one common bus line even in intrinsically-safe areas. PROFIBUS-PA
permits data communication and power over the bus using a 2-wire technology according to the
international standard IEC 1158-2.
PROFIBUS-FMS
PROFIBUS-FMS is the general-purpose solution for communication tasks at the cell level.
Powerful FMS services open up a wide range of applications and provide great flexibility.
PROFIBUS-FMS can also be used for extensive and complex communication tasks.
PROFIBUS specifies the technical and functional characteristics of a serial fieldbus system with which
decentralized digital controllers can be networked together from the field level to the cell level.
PROFIBUS distinguishes between master devices and slave devices.
Master devices determine the data communication on the bus. A master can send messages without an
external request when it holds the bus access rights (the token). Masters are also called active stations
in the PROFIBUS protocol.
Slave devices are peripheral devices. Typical slave devices include input/output devices, valves, drives
and measuring transmitters. They do not have bus access rights and they can only acknowledge
received messages or send messages to the master when requested to do so. Slaves are also called
passive stations.
3.2 Profiles
The PROFIBUS-DP protocol defines how user data are to be transmitted between the stations over the
bus. User data are not evaluated by the PROFIBUS-DP transmission protocol. The meaning is
specified in the profiles. In addition, the profiles specify how PROFIBUS-DP is to be used in the
application area. The following PROFIBUS-DP profile is used in VACON CX Profibus fieldbus board.
Variable-Speed Drive Profile (3.071)
Leading manufacturers of drive technology have jointly defined the PROFIDRIVE profile. The profile
specifies how the drives are to be parameterized and how the setpoints and actual values are to be
transmitted. This enables drives from different vendors to be exchanged. The profile contains necessary
specifications for speed control and positioning. It specifies the basic drive functions while leaving
sufficient freedom for application-specific expansions and further developments. The profile describes
the mapping of the application functions for DP or FMS.