Siemens DS III PROFIsafe Series User manual

Introduction
1
General safety instructions
2
Device-specific safety
instructions
3
Appendix
A
List of
Abbreviations/Acronyms
B
SITRANS
Pressure transmitter
Functional safety for SITRANS P,
series DS III PROFIsafe
Product information
07/2006
A5E00849297-01
Supplement to the Operating Instructions

Safety Guidelines
This manual contains notices you have to observe in order to ensure your personal safety, as well as to prevent
damage to property. The notices referring to your personal safety are highlighted in the manual by a safety alert
symbol, notices referring only to property damage have no safety alert symbol. These notices shown below are
graded according to the degree of danger.
Danger
indicates that death or severe personal injury will result if proper precautions are not taken.
Warning
indicates that death or severe personal injury may result if proper precautions are not taken.
Caution
with a safety alert symbol, indicates that minor personal injury can result if proper precautions are not taken.
Caution
without a safety alert symbol, indicates that property damage can result if proper precautions are not taken.
Notice
indicates that an unintended result or situation can occur if the corresponding information is not taken into
account.
If more than one degree of danger is present, the warning notice representing the highest degree of danger will
be used. A notice warning of injury to persons with a safety alert symbol may also include a warning relating to
property damage.
Qualified Personnel
The device/system may only be set up and used in conjunction with this documentation. Commissioning and
operation of a device/system may only be performed by qualified personnel. Within the context of the safety notes
in this documentation qualified persons are defined as persons who are authorized to commission, ground and
label devices, systems and circuits in accordance with established safety practices and standards.
Prescribed Usage
Note the following:
Warning
This device may only be used for the applications described in the catalog or the technical description and only in
connection with devices or components from other manufacturers which have been approved or recommended by
Siemens. Correct, reliable operation of the product requires proper transport, storage, positioning and assembly
as well as careful operation and maintenance.
Trademarks
All names identified by ® are registered trademarks of the Siemens AG. The remaining trademarks in this
publication may be trademarks whose use by third parties for their own purposes could violate the rights of the
owner.
Disclaimer of Liability
We have reviewed the contents of this publication to ensure consistency with the hardware and software
described. Since variance cannot be precluded entirely, we cannot guarantee full consistency. However, the
information in this publication is reviewed regularly and any necessary corrections are included in subsequent
editions.
Siemens AG
Automation and Drives
Postfach 48 48
90437 NÜRNBERG
GERMANY
Order No.: A5E00849297-01
Edition 08/2006
Copyright © Siemens AG 2006.
Technical data subject to change

Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 iii
Table of contents
1 Introduction............................................................................................................................................. 1-1
1.1 Purpose of this document .......................................................................................................... 1-1
1.2 Scope of this document ............................................................................................................. 1-1
1.3 History........................................................................................................................................ 1-1
1.4 Further information..................................................................................................................... 1-2
2 General safety instructions ..................................................................................................................... 2-1
2.1 Safety-instrumented system ...................................................................................................... 2-1
2.2 Safety Integrity Level (SIL)......................................................................................................... 2-2
3 Device-specific safety instructions .......................................................................................................... 3-1
3.1 Application range ....................................................................................................................... 3-1
3.2 Safety function ........................................................................................................................... 3-2
3.3 Settings ...................................................................................................................................... 3-3
3.4 Behavior in case of faults........................................................................................................... 3-4
3.5 Maintenance/Checking .............................................................................................................. 3-4
3.6 Safety characteristics................................................................................................................. 3-5
A Appendix.................................................................................................................................................A-1
A.1 Literature and standards ............................................................................................................A-1
A.2 SIL Declaration of Conformity....................................................................................................A-2
A.3 Test report (excerpt) ..................................................................................................................A-5
B List of Abbreviations/Acronyms...............................................................................................................B-1
B.1 Abbreviations .............................................................................................................................B-1
Glossary ..................................................................................................................................... Glossary-1
Index................................................................................................................................................ Index-1
Tables
Table 2-1 Safety Integrity Level ................................................................................................................. 2-3

Table of contents
Functional safety for SITRANS P, series DS III PROFIsafe
iv Product information, 07/2006, A5E00849297-01

Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 1-1
Introduction 1
1.1 Purpose of this document
This document contains information and safety notes that you will require when using the
pressure transmitter in safety-instrumented systems.
It is aimed at persons who install the device mechanically, connect it electrically,
parameterize and commission it, as well as at service and maintenance engineers.
1.2 Scope of this document
This document deals with the pressure transmitters exclusively as a part of a safety function.
This documentation is applicable only in connection with the following documentation:
No. Name Order number
/1/ Operating Instructions for SITRANS P, series DS III PA A5E00053276
1.3 History
This history establishes the correlation between the current documentation and the valid
firmware of the device.
The documentation of this edition is applicable for the following firmware:
Edition Firmware identification type
plate
System integration Installation path for PDM
01
06/2006
FW: from 301.02.01K PDM V 6.0.2;
DD version 01.02.01.50
SITRANS P DS III PA
PROFIsafe
The most important changes in the documentation when compared with the respective
previous edition are given in the following table.
Edition Remark
01
06/2006
First edition

Introduction
1.4 Further information
Functional safety for SITRANS P, series DS III PROFIsafe
1-2 Product information, 07/2006, A5E00849297-01
1.4 Further information
Information
The contents of these instructions shall not become part of or modify any prior or existing
agreement, commitment or legal relationship. All obligations on the part of Siemens AG are
contained in the respective sales contract which also contains the complete and solely
applicable warranty conditions. Any statements contained herein do not create new
warranties or modify the existing warranty.
The content reflects the technical status at the time of printing. We reserve the right to make
technical changes in the course of further development.
Siemens Regional Offices
If you need more information or have particular problems which are not covered sufficiently
by the operating instructions, contact your local Siemens Regional Office. You will find the
address of your local Siemens Regional Office on the Internet.
Product information on the Internet
The Programming Manual forms a part of the supplied CD and is also available on the
Siemens homepage on the Internet.
On the supplied CD, you will also find the technical data sheet containing the ordering data,
the Device Install software for SIMATIC PDM for subsequent installation and the generic
station description (GSD).
See also
Siemens Regional Offices (www.siemens.com/processinstrumentation/contacts)
Product information on the Internet (http://www.siemens.com/sitransp)
Instructions and Manuals (http://www.siemens.com/processinstrumentation/documentation)

Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 2-1
General safety instructions 2
2.1 Safety-instrumented system
Definition: Safety-instrumented system
A safety-instrumented system executes the safety functions that are required to achieve or
maintain a safe status in a system. It consists of a sensor, logic unit/control system and final
controlling element.
Example:
A safety-instrumented system is made up of a pressure transmitter, a limit signal sensor and
a control valve.
Definition: Safety function
Defined function executed by a safety-instrumented system with the objective of achieving or
maintaining a safe system status taking into account a defined dangerous occurrence.
Example:
Limit pressure monitoring
Definition: Dangerous failure
Failure with the potential to bring the safety-instrumented system into a dangerous or non-
functional status.
Description
The sensor, logic unit/control system and final controlling element combine to form a safety-
instrumented system, which executes a safety function.
Note
This document deals with the SITRANS P pressure transmitter exclusively as a part of a
safety function.

General safety instructions
2.2 Safety Integrity Level (SIL)
Functional safety for SITRANS P, series DS III PROFIsafe
2-2 Product information, 07/2006, A5E00849297-01
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Figure 2-1 Example of a safety-instrumented system with a bus
Functioning of the system as shown in the example
The transmitter generates a process-specific measured value. The programmable logic
control (PLC) monitors this value in case it exceeds a preset limit value. If a fault occurs, the
PLC generates a shutdown signal for the connected positioner. The positioner switches the
corresponding valve to the defined safety position. The communication with the positioner
via PROFIBUS PA or FOUNDATION Fieldbus remains unrestricted, i.e. position and status
messages are still possible.
2.2 Safety Integrity Level (SIL)
Definition: SIL
The international standard IEC 61508 defines four discrete Safety Integrity Levels (SIL) from
SIL 1 to SIL 4. Each level corresponds to the probability range for the failure of a safety
function. The higher the SIL of the safety-instrumented system, the higher probability that the
required safety function will work.

General safety instructions
2.2 Safety Integrity Level (SIL)
Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 2-3
The achievable SIL is determined by the following safety characteristics:
•Average probability of dangerous failure of a safety function in case of demand (PFDAVG)
•Hardware fault tolerance (HFT)
•Safe failure fractions (SFF)
Description
The following table shows the dependency of the SIL on the "average probability of
dangerous failures of a safety function of the entire safety-instrumented system" (PFDAVG)
The table deals with "Low demand mode", i.e. the safety function is required a maximum of
once per year on average.
Table 2-1 Safety Integrity Level
SIL PFD
AVG
4 ≥ 10-5...< 10-4
3 ≥ 10-4...< 10-3
2 ≥ 10-3...< 10-2
1 ≥ 10-2...< 10-1
The "average probability of dangerous failures of the entire safety-instrumented system"
(PFDAVG) is normally split between the three sub-systems in the following figure.
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Figure 2-2 Example of PFD distribution
The following table shows the achievable Safety Integrity Level (SIL) for the entire safety-
instrumented system for type B subsystems depending on the safe failure fraction (SFF) and
the hardware fault tolerance (HFT). Type B subsystems include analog transmitters and
shut-off valves without complex components, e.g. microprocessors (also see IEC 61508,
Section 2).
HFT SFF
0 1 (0) 1) 2 (1)
1)
< 60 % Not permissible SIL 1 SIL 2
60 to 90 % SIL 1 SIL 2 SIL 3
90 to 99 % SIL 2 SIL 3 SIL 4
> 99 % SIL 3 SIL 4 SIL 4
1) As per IEC 61511-1, Section 11.4.4

General safety instructions
2.2 Safety Integrity Level (SIL)
Functional safety for SITRANS P, series DS III PROFIsafe
2-4 Product information, 07/2006, A5E00849297-01
As per IEC 61511-1, Section 11.4.4, the hardware fault tolerance (HFT) can be reduced by
one (values in brackets) for sensors and final controlling elements with complex components
if the following conditions are applicable for the device:
•The device is ready for operation.
•The user can configure only the process-related parameters, e.g. control range, signal
direction in case of a fault, limiting values, etc.
•The configuration level of the firmware is blocked against unauthorized operation.
•The function requires SIL of less than 4.
The pressure transmitter fulfills these conditions.
See also
Safety characteristics (Page 3-5)

Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 3-1
Device-specific safety instructions 3
3.1 Application range
Overview
The pressure transmitter is available in versions like gauge pressure, differential pressure
and absolute pressure. The output signal is a process-specific digital measured value. The
measured value is displayed with the associated status. The pressure transmitter measures
corrosive, non-corrosive and hazardous gases, vapors and liquids.
You can use them for the following measurement types:
•Gauge pressure
•Differential pressure
•Absolute pressure from the gauge pressure breaker range
•Absolute pressure from the differential pressure breaker range
With appropriate parameterization, you can also use it for the following additional
measurement types:
•Level
•Volume
•Mass
•Flow
You can install the transmitter of the appropriate version having the "intrinsically safe" type of
protection EEx ia, EEx ib or "flameproof enclosure" EEx d in hazardous areas, on zone 0
and in zones 1 or 2. Devices have an EC-type examination certificate and fulfill the
corresponding harmonized standards, e.g. European CENELEC.
Gauge pressure
This version measures the gauge pressure of corrosive, non-corrosive and hazardous
gases, vapors and liquids.
Differential pressure
This version measures:
•Differential pressure
•Positive or negative gauge pressure
•A flow rate with q ∼
S
GLII
, together with a throttling device
It measures the pressure of corrosive, non-corrosive and hazardous gases, vapors and
liquids.

Device-specific safety instructions
3.2 Safety function
Functional safety for SITRANS P, series DS III PROFIsafe
3-2 Product information, 07/2006, A5E00849297-01
Level
The gauge pressure or differential pressure version measures the level of corrosive, non-
corrosive and hazardous liquids with the help of appropriate parameterization.
Wetted parts are made from different materials depending on the required corrosion
resistance.
Flow
The differential pressure version measures the flow rate of corrosive, non-corrosive and
hazardous liquids with the help of appropriate parameterization.
Wetted parts are made from different materials depending on the required corrosion
resistance.
Absolute pressure
These versions measure the absolute pressure of corrosive, non-corrosive and hazardous
gases, vapors and liquids.
Requirements
These pressure transmitters meet the following requirements:
•Functional safety to SIL 2 under IEC 61508 or IEC 61511-1, from firmware version FW:
from 301.02.01K
•Explosion protection for corresponding versions
•Electromagnetic compatibility in compliance with EN 61326
3.2 Safety function
Safety function for pressure transmitters
Measuring pressures is the safety function for SITRANS P. The pressure is converted to a
digital measured value and transmitted by PROFIsafe communication. The measured value
has an accuracy of ±2%. It is transmitted together with the status information "Validity" and
"Quality". The safety function ensures that the diagnostic functions respond and signal an
invalid measured value within 60 seconds in the worst case scenario.

Device-specific safety instructions
3.3 Settings
Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 3-3
Warning
The binding settings and conditions are listed in the "Settings" and "Safety characteristics"
sections.
These conditions must be met in order to fulfill the safety function.
The calculated Mean Time Between Failures (MTBF) for the SITRANS P pressure
transmitter is approximately 282 years.
See also
Settings (Page 3-3)
Safety characteristics (Page 3-5)
3.3 Settings
The following settings must be adhered to after installing and commissioning as per the
Operating Instructions:
Operation/configuration
While operating/configuring, ensure that the technical data of the pressure transmitter are
adhered to in their respective version.
Checking the safety function
We recommend that:
•You check the status for warnings and alarms.
•You check the measured value limits.
•Simulate various measured values and statuses.
•You check the measuring accuracy that must be in the range of ± 2% for the safety
function.
–You check the zero point, e.g. in a pressure-less state, for gauge and differential
pressure.
–You check the zero point, e.g. with a defined pressure, for absolute pressure.
Protection against configuration changes
After parameterizing/commissioning:
1. Set the lock mode in Mode 10 to write protection "L".
Operation via buttons and PROFIBUS communication is blocked.
2. Protect the keys from unintended change in the parameters, e.g. by lead-sealing.

Device-specific safety instructions
3.4 Behavior in case of faults
Functional safety for SITRANS P, series DS III PROFIsafe
3-4 Product information, 07/2006, A5E00849297-01
Reference
You can find the operating instructions in the following documentation:
Operating instructions SITRANS P, series DS III PA
Order number A5E00053276
3.4 Behavior in case of faults
Repairs
Defective devices should be sent in to the repair department with details of the fault and the
cause. When ordering replacement devices, please specify the serial number of the original
device. The serial number can be found on the rating plate.
The address of the responsible SIEMENS repair center, contacts, spare parts lists, etc. can
be found on the Internet.
See also
Services & Support (http://www.siemens.com/automation/services&support)
Partner (http://www.automation.siemens.com/partner)
3.5 Maintenance/Checking
Interval
We recommend that the functioning of the pressure transmitter be checked at regular
intervals of one year.
Checking the safety function
We recommend that:
•You check the status for warnings and alarms.
•You check the measured value limits.
•Simulate various measured values and statuses.
•You check the measuring accuracy that must be in the range of ± 2% for the safety
function.
–You check the zero point, e.g. in a pressure-less state, for gauge and differential
pressure.
–You check the zero point, e.g. with a defined pressure, for absolute pressure.

Device-specific safety instructions
3.6 Safety characteristics
Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 3-5
Checking safety
You should regularly check the safety function of the entire safety circuit in line with IEC
61508/61511. The testing intervals are determined during the calculation for each individual
safety circuit in a system (PFDAVG).
Electronics
The safety function of the transmitter is ensured only with the electronics delivered by the
factory. It cannot be replaced.
3.6 Safety characteristics
The safety characteristics necessary for using the system are listed in the "SIL declaration of
conformity". These values apply under the following conditions:
•The SITRANS P pressure transmitter is only used in applications with a low demand rate
for the safety function (low demand mode).
•The safety-related parameters/settings have been entered by local operation or
PROFIBUS communication before commencing safety-instrumented operation. They are
checked on the local display.
(see "Settings" section)
•The safety function test is concluded successfully.
•The transmitter is blocked against unwanted and unauthorized changes/operation.
•The measured values transmitted with PROFIsafe are evaluated by a secure system.
•The calculation of fault rates is based on a MTTR of 8 hours.
See also
Settings (Page 3-3)
SIL Declaration of Conformity (Page A-2)

Device-specific safety instructions
3.6 Safety characteristics
Functional safety for SITRANS P, series DS III PROFIsafe
3-6 Product information, 07/2006, A5E00849297-01

Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 A-1
Appendix A
A.1 Literature and standards
No. Standard Description
/1/ IEC 61508
Section 1-7
Functional safety of following systems:
•Safety-instrumented
•Electrical
•Electronic
•Programmable
Target group:
Manufacturers and suppliers of equipment
/2/ IEC 61511
Section 1-3
Functional safety - Safety systems for the process industry
Target group:
Planners, constructors and users

Appendix
A.2 SIL Declaration of Conformity
Functional safety for SITRANS P, series DS III PROFIsafe
A-2 Product information, 07/2006, A5E00849297-01
A.2 SIL Declaration of Conformity

Appendix
A.2 SIL Declaration of Conformity
Functional safety for SITRANS P, series DS III PROFIsafe
Product information, 07/2006, A5E00849297-01 A-3

Appendix
A.2 SIL Declaration of Conformity
Functional safety for SITRANS P, series DS III PROFIsafe
A-4 Product information, 07/2006, A5E00849297-01