Pepperl+Fuchs KFD2-UT2 Series User manual

ISO9001
2
Functional Safety
Temperature Converter
KFD2-UT2-(Ex)*(-1)
PROCESS AUTOMATION
MANUAL

With regard to the supply of products, the current issue of the following document is applicable: The General Terms of
Delivery for Products and Services of the Electrical Industry, published by the Central Association of the Electrical
Industry (Zentralverband Elektrotechnik und Elektroindustrie (ZVEI) e.V.) in its most recent version as well as the
supplementary clause: "Expanded reservation of proprietorship"
Functional Safety KFD2-UT2-(Ex)*(-1)

Functional Safety KFD2-UT2-(Ex)*(-1)
Content
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1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1 Content of this Document. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.3 Symbols Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 Product Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1 Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3 Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.4 Standards and Directives for Functional Safety . . . . . . . . . . . . . . . . . . 8
3 Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1 System Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Assumptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3 Safety Function and Safe State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.4 Characteristic Safety Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.5 Useful Lifetime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4 Mounting and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.1 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1 Proof Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2 Proof Test Procedure for KFD2-UT2-(Ex)*(-1) . . . . . . . . . . . . . . . . . . 16
6 Maintenance and Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
7 List of Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

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Functional Safety KFD2-UT2-(Ex)*(-1)
Introduction
1 Introduction
1.1 Content of this Document
This document contains information for usage of the device in functional safety-related
applications. You need this information to use your product throughout the applicable stages
of the product life cycle. These can include the following:
• Product identification
• Delivery, transport, and storage
• Mounting and installation
• Commissioning and operation
• Maintenance and repair
• Troubleshooting
• Dismounting
• Disposal
The documentation consists of the following parts:
• Present document
• Instruction manual
• Manual
• Datasheet
Additionally, the following parts may belong to the documentation, if applicable:
• EU-type examination certificate
• EU declaration of conformity
• Attestation of conformity
• Certificates
• Control drawings
• FMEDA report
• Assessment report
• Additional documents
For more information about Pepperl+Fuchs products with functional safety,
see www.pepperl-fuchs.com/sil.
Note
This document does not substitute the instruction manual.
Note
For full information on the product, refer to the instruction manual and further documentation
on the Internet at www.pepperl-fuchs.com.

Functional Safety KFD2-UT2-(Ex)*(-1)
Introduction
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1.2 Safety Information
Target Group, Personnel
Responsibility for planning, assembly, commissioning, operation, maintenance,
and dismounting lies with the plant operator.
Only appropriately trained and qualified personnel may carry out mounting, installation,
commissioning, operation, maintenance, and dismounting of the product.
The personnel must have read and understood the instruction manual
and the further documentation.
Intended Use
The device is only approved for appropriate and intended use. Ignoring these instructions
will void any warranty and absolve the manufacturer from any liability.
The device is developed, manufactured and tested according to the relevant safety standards.
Use the device only
• for the application described
• with specified environmental conditions
• with devices that are suitable for this safety application
Improper Use
Protection of the personnel and the plant is not ensured if the device is not used according
to its intended use.

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Functional Safety KFD2-UT2-(Ex)*(-1)
Introduction
1.3 Symbols Used
This document contains symbols for the identification of warning messages
and of informative messages.
Warning Messages
You will find warning messages, whenever dangers may arise from your actions.
It is mandatory that you observe these warning messages for your personal safety and in order
to avoid property damage.
Depending on the risk level, the warning messages are displayed in descending order
as follows:
Informative Symbols
Action
This symbol indicates a paragraph with instructions. You are prompted to perform an action
or a sequence of actions.
Danger!
This symbol indicates an imminent danger.
Non-observance will result in personal injury or death.
Warning!
This symbol indicates a possible fault or danger.
Non-observance may cause personal injury or serious property damage.
Caution!
This symbol indicates a possible fault.
Non-observance could interrupt the device and any connected systems and plants,
or result in their complete failure.
Note
This symbol brings important information to your attention.

Functional Safety KFD2-UT2-(Ex)*(-1)
Product Description
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2 Product Description
2.1 Function
KFD2-UT2-*(-1)
This signal conditioner provides the galvanic isolation between field circuits and
control circuits.
The device converts the signal of a resistance thermometer, thermocouple, or potentiometer
to a proportional output current.
The device can also be configured as a signal splitter.
The removable terminal block K-CJC-** is available as an accessory for internal cold junction
compensation of thermocouples.
A fault is signalized by LEDs and a separate collective error message output.
The device is easily configured by the use of the PACTware configuration software.
The device is mounted on a 35 mm DIN mounting rail according to EN 60715.
KFD2-UT2-*-1
The device converts the signal of a resistance thermometer, thermocouple, or potentiometer
to a proportional output voltage.
KFD2-UT2-Ex*(-1)
This isolated barrier is used for intrinsic safety applications.
The device converts the signal of a resistance thermometer, thermocouple, or potentiometer
to a proportional output current.
The device can also be configured as a signal splitter.
The removable terminal block K-CJC-** is available as an accessory for internal cold junction
compensation of thermocouples.
A fault is signalized by LEDs and a separate collective error message output.
The device is easily configured by the use of the PACTware configuration software.
The device is mounted on a 35 mm DIN mounting rail according to EN 60715.
KFD2-UT2-Ex*-1
The device converts the signal of a resistance thermometer, thermocouple, or potentiometer
to a proportional output voltage.

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Functional Safety KFD2-UT2-(Ex)*(-1)
Product Description
2.2 Interfaces
The device has the following interfaces.
• Safety relevant interfaces:
• Input I, input II (only 2-channel version)
• Output I, output II (only 2-channel version)
• Non-safety relevant interfaces: programming socket, collective error message output
2.3 Marking
2.4 Standards and Directives for Functional Safety
Device specific standards and directives
System-specific standards and directives
Note
For corresponding connections see datasheet.
Pepperl+Fuchs Group
Lilienthalstraße 200, 68307 Mannheim, Germany
Internet: www.pepperl-fuchs.com
KFD2-UT2-1, KFD2-UT2-1-1, KFD2-UT2-2, KFD2-UT2-2-1 Up to SIL 2
KFD2-UT2-Ex1, KFD2-UT2-Ex1-1,KFD2-UT2-Ex2, KFD2-UT2-Ex2-1
Functional safety IEC/EN 61508, part 2 and 3, edition 2010:
Functional safety of electrical/electronic/programmable
electronic safety-related systems (manufacturer)
Functional safety IEC 61511-1:2016+COR1:2016+A1:2017
EN 61511-1:2017+A1:2017
Functional safety –Safety instrumented systems
for the process industry sector (user)

Functional Safety KFD2-UT2-(Ex)*(-1)
Planning
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3 Planning
3.1 System Structure
3.1.1 Low Demand Mode of Operation
If there are two control loops, one for the standard operation and another one for the functional
safety, then usually the demand rate for the safety loop is assumed to be less
than once per year.
The relevant safety parameters to be verified are:
• the PFDavg value (average Probability of dangerous Failure on Demand)
and the T1value (proof test interval that has a direct impact on the PFDavg value)
• the SFF value (Safe Failure Fraction)
• the HFT architecture (Hardware Fault Tolerance)
3.1.2 High Demand or Continuous Mode of Operation
If there is only one safety loop, which combines the standard operation and safety-related
operation, then usually the demand rate for this safety loop is assumed to be higher
than once per year.
The relevant safety parameters to be verified are:
• the PFH value (Probability of dangerous Failure per Hour)
• Fault reaction time of the safety system
• the SFF value (Safe Failure Fraction)
• the HFT architecture (Hardware Fault Tolerance)
3.1.3 Safe Failure Fraction
The safe failure fraction describes the ratio of all safe failures and dangerous detected failures
to the total failure rate.
SFF = (s + dd) / (s + dd + du)
A safe failure fraction as defined in IEC/EN 61508 is only relevant for elements or (sub)systems
in a complete safety loop. The device under consideration is always part of a safety loop but
is not regarded as a complete element or subsystem.
For calculating the SIL of a safety loop it is necessary to evaluate the safe failure fraction
of elements, subsystems and the complete system, but not of a single device.
Nevertheless the SFF of the device is given in this document for reference.

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Functional Safety KFD2-UT2-(Ex)*(-1)
Planning
3.2 Assumptions
The following assumptions have been made during the FMEDA:
• Failure rate based on the Siemens standard SN 29500.
• Failures during configuration are not considered.
• The collective error message output is not considered in the FMEDA and
in the calculations.
• Propagation of failures is not relevant.
• External power supply failure rates are not included.
• The collective error message output is not safety relevant.
• The indication of a dangerous failure (via fault bus) is detected within 1 hour
by the programmable logic controller (PLC).
• Only one input and one output are part of the safety function (only for 2-channel version).
• The device will be used under average industrial ambient conditions comparable
to the classification "stationary mounted" according to MIL-HDBK-217F.
Alternatively, operating stress conditions typical of an industrial field environment similar
to IEC/EN 60654-1 Class C with an average temperature over a long period of time
of 40 ºC may be assumed. For a higher average temperature of 60 ºC, the failure rates
must be multiplied by a factor of 2.5 based on experience. A similar factor must be used
if frequent temperature fluctuations are expected.
• The application program in the programmable logic controller (PLC) is configured to detect
underrange and overrange failures. These failures have been classified as dangerous
detected failures.
SIL 2 Application
• To build a SIL safety loop for the defined SIL, it is assumed as an example that this device
uses 10 % of the available budget for PFDavg/PFH.
• For a SIL 2 application operating in low demand mode the total PFDavg value of
the SIF (Safety Instrumented Function) should be smaller than 10-2, hence the maximum
allowable PFDavg value would then be 10-3.
• According to IEC/EN 61511-1 section 11.4.5, a HFT = 0 can be considered sufficient for
SIL 2 applications in low demand mode of operation. The evaluation is based on failure
rates as described in section 11.9.