WESTLOCK CONTROLS CORPORATION
280 N. MIDLAND AVE., STE. 258, SADDLE BROOK, NJ 07663 TEL: 201-794-7650 FAX: 201-794-0913
www.westlockcontrols.com
10/5/2013
TECH-477/D.W.O. 21424
Page 52 of 206
8 Fieldbus Network
8.1 PROFIBUS Overview
8.1.1 About PROFIBUS PA
PROFIBUS PA is a standard fieldbus communication where the communication and the
power go to the device thought a twist par cable. The IEC 61158 defines the standard for
PROFIBUS. The profile 3.02 make even easier the manipulation of field devices when a
replace is needs. The new device takes the role of its predecessor automatically
2
.
8.2 PROFIBUS PA – Profile
A PA device and its functions are structured in Physical bock, Transducer Block and
Function blocks objects.
The device has some rules to following and it shall follow:
a) The PROFIBUS protocol specification according to IEC 61784-1 CP 3/1 and CP 3/2
and
b) The profile specification according to Profile for Process Control Devices – Version
3.02 – April 2009
A generic structure of a PROFIBUS PA device is:
8.3 The Function Blocks Application
Device functionalities are modeled by Function Blocks; each device performs a part of this
functionality in a fieldbus segment, such a sensor acquisition, and control algorithm and
2
See PI Organization documents for more details. Website:
http://www.profibus.com