PROFIsafe on PROFIBUS DP and PROFINET IO
PROFINET , PROFIBUS , PROFIsafe
While automation solutions with distributed I/O gained widely acceptance through PROFIBUS DP and the PROFINET IO, classic safety applications were still relying on a second layer of conventional (electro-mechnic) techniques or special busses thus limiting the seamless engineering and interoperability. Additionally modern functional safety devices such as laser scanners or drives with integrated safety could not be fueled up as needed due to missing system support. It is the purpose of the PROFIsafe specifications and related documents to provide the corresponding enabling technologies.The specific utilization of the communication functions by specific groups of participants is called a profile. A profile is a set of rules and definitions that are valid within a group of users or a family of field devices. The Safety Profile, in short PROFIsafe, describes the communications between functional safety peripherals ("F-Devices") and functional safety controllers ("F-Hosts"). It is a supplementary technology for standard PROFIBUS DP and PROFINET IO reducing the residual failure or error rate of the data transmission between an F-Host and an F-Device to the level required by the relevant standards (IEC61784-3), or better.
During the past few years the PROFIsafe community raised requirements for new features and changes such as:
- "Channel granular passivation" in conjunction with the qualifier bits specified within a new PI profile "RIO for FA";
- an option to extend once only the PROFIsafe timeout (F_WD_Time) in case of "configuration in run" (F_WD_Time_2);
- improvements for CRC signature calculations within GSD files via harmonized calculation algorithms;
- protocol extensions (LP) to protect against possible loopback threads;
- (optional) protocol modifications by means of random and disjoint Codename based MonitoringNumbers instead of consecutive numbering in order to improve SIL conditions in case of large numbers of participants;
- additional standardized diagnosis types;
- removal of the V1-mode (legacy systems); and
- diverse error corrections, fixes of typos, and reference updates.
These activities lead to a new version 2.6 of the PROFIsafe profile specification which was published in November 2013. An intermediate version 2.5 has been withdrawn. The mandatory clause "Management summary – scope of this document" for PNO documents is covered by the clauses "INTRODUCTION" and "Scope".Known patents are listed in clause "INTRODUCTION". Version 2.6 is the basis for edition 3 of the IEC 61784-3-3, which is now in CD state (committee draft, see www.iec.ch).
PROFIsafe version 2.4 has been effective since 2007 and will still be the basis for test and certification of F-Hosts and F-Devices as long as updates of development kits and automated testers are not available. Availability can be inquired at the PROFIsafe competence/test centers or at the PI support center.IEC rules do not permit the request for certification. However, the PROFIsafe policy in PI requires test and certification of PROFIsafe devices. The corresponding requirements are specified in "PROFIsafe – Test Specification for F-Slaves, F-Devices, and F-Hosts", Order No. 2.242, which will soon be updated to meet PROFIsafe V2.6.
We point to the IEC 61784-3, which comprises general information on functional safety communication principles and provides common definitions and principles for all different profiles. PI will not continue publishing its information via order number 3.192a since it is available through IEC channels (www.iec.ch).
Version: 2.4 (still effective for development, test & certification until the availability of updated development kits and test equipment according V2.6)
Order No.: 3.192b
Order No.: 3.192