Profibus-Dp; Functions - Ecolab 202580 Manual De Instrucciones

3.4

PROFIBUS-DP

PROFIBUS-DP is designed for high-speed data exchange at the field level.
The central control devices, PLC/PC for instance, communicate through a fast serial
connection with distributed field devices such as I/O, paperless recorders and controllers.
Data exchange with these distributed devices is mainly cyclic.
Communication functions required for this purpose are defined by the basic
PROFIBUS-DP functions in accordance with IEC 61158 and IEC 61784.
Basic functions
The central control system (master) reads the input information from the slaves cyclically
and writes the output information to the slaves cyclically. The bus cycle time must be
shorter than the program cycle time of the central PLC.
In addition to cyclic user data transmission, PROFIBUS-DP also provides powerful
functions for diagnostics and commissioning.
Transmission technology:
RS485, twisted pair cable
n
n Baud rates of 9.6 Kbit/s up to 12 Mbit/s
Bus access:
n Master and slave devices, max. 126 stations on one bus
Communication:
n Peer-to-peer (user data communication)
n Cyclic master-slave user data communication
Operating states:
n Operate: Cyclic transmission of input and output data
Clear: Inputs are read, outputs remain in a secure state
n
n Stop: Only master-master data transfer is possible
Synchronization:
n Sync mode: is not supported
Freeze mode: is not supported
n

Functions:

n Cyclic user data transfer between DP master and DP slave(s)
n Dynamic activation or deactivation of individual DP slaves
n Checking the configuration of the DP slaves
n Address assignment for the DP slaves via the bus (is not supported)
n Configuration of the DP master via the bus
n Maximum of 176 bytes of input/output data for each DP slave possible
Protective functions:
n Response monitoring for the DP slaves
n Access protection for inputs/outputs of the DP slaves
n Monitoring of the user data communication with adjustable monitoring timer in the DP
master
Device types:
DP master class 2, e. g. programming/project design devices
n
n DP master class 1, e. g. central automation devices (PLC, PC)
n DP slave, e. g. devices with binary or analog inputs/outputs, controllers, recorders
Probifus-DP description
19 417102396 Rev. 1-10.2019