Profile; Interfacing - Siemens PROFIBUS PA SIPART PS2 Manual

1.2.4 Profile

Control room
PLS, PC
T Terminating resistor
FD Field device
PC Personal computer
PLS Process control system
Figure 1-6 PROFIBUS PA-architecture

1.2.5 Interfacing

SIPART PS2 PA Manual
A5E00127926-03
Supplementary to the EN standard 50170, the PNO (PROFIBUS User-
organisation) has defined the functionality of the individual field device
types in a so-called profile description. This profile defines minimum
functional requirements and optional extensions. The device-internal
Device Management supplies all the basic information necessary for
finding the profile parameters to the control system configuration tool.
With this, a parametering tool can operate all profile-conforming de-
vices regardless of type and manufacturer.
Depending on the size of the system and thus the number of field de-
vices and the required timing, the system must be implemented with
one or more PROFIBUS-PA channels. A PROFIBUS PA channel con-
sists of the components shown in Figure 1-6.
PROFIBUS-DP
Coupler
T
Power
supply
The central process control system PLS or, in the case of low require-
ments, a PC, is responsible for the control.
As a rule the signal conversion DP/PA, bus feeding and bus termination
functions are combined in a coupling module. Depending on the num-
ber of PROFIBUS-A field devices to be operated in the automation sys-
tem and the required timing, a DP/PA coupler or, in the case of higher
requirements, a more powerful DP/PA link is used.
Field
PROFIBUS-PA
FD FD
Introduction
T
additional
cable ter-
mination
19