wilamowski-b-m-irwin-j-d-industrial-communication-systems-2011

46
Profisafe
Ron Mitchell
RC Systems
Max Felser
Bern University of
Applied Sciences
Paulo Portugal
University of Porto
46.1 Introduction.....................................................................................46-1
Standardization Framework. •. Black Channel Principle
46.2 Profisafe Communication..............................................................46-3
Error-Detection Requirements. •. Error Types and Safeguards. •. .
Cyclic/Acyclic Communication. •. Cyclic Communication
PDU. •. Virtual Consecutive Number. •. Time-Out with
Receipt. •. Code Name for Sender/Receiver. •. Data Consistency
Check. •. Detected Safety Data Failures
46.3 Deployment....................................................................................46-11
Power Supplies and Electrical Safety. •. Increased Immunity. •. .
Installation Guidelines. •. Wireless Transmission
and Security. •. Response Time
Acronyms...................................................................................................46-14
References..................................................................................................46-14
46.1 Introduction
Profisafe is a comprehensive and integrated solution with the aim to support safe communication in
fieldbus networks (Figure 46.1). Profisafe comprises the following principles [1]:
• Integration of safety-related applications into standard solutions without any impact for the latter
ones.
• Standard and safety data coexist in the same network—Profibus (see Chapter 32) or Profinet
(see Chapter 40)—without modification of the standard protocols.
• Safety data is transmitted between safety equipment—controllers (F-Host) and devices
(F-Device)—using the highest integrity level (SIL 3 or PL “e”) required by current applications in
factory and process automation.
• Configuration, parameterization, diagnosis, and maintenance of safety devices is performed
using engineering tools that are similar to those employed in standard applications, thus facilitating
the development and integration process.
46.1.1 Standardization Framework
The development of safety-related systems for factory and process automation is a complex task, which
involves the employment of multiple and interrelated standards. Figure 46.2 presents a selection of the
most relevant ones.
The development of Profisafe was performed based on two standards: IEC 61508 [2] and EN 50159-1,
now IEC 62280-1 [3]. IEC 61508 outlines the requirements when electrical/electronic/programmable
electronic systems are used to perform safety functions (further details can be found in Chapter 2),
46-1
© 2011 by Taylor and Francis Group, LLC