Pepperl+Fuchs KFD2-ELD-Ex16 User manual

ISO9001
Functional Safety
Ground Fault Detection
KFD2-ELD-(Ex)16
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-ELD-(Ex)16

Functional Safety KFD2-ELD-(Ex)16
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
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 . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Characteristic Safety Values. . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.5 Useful Life Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4 Mounting and Installation . . . . . . . . . . . . . . . . . . . . . . . . 12
4.1 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5 Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1 Proof Test Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6 Maintenance and Repair . . . . . . . . . . . . . . . . . . . . . . . . . 14
7 List of Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Functional Safety Manual HiD2872, HiC2873(Y1), HiD2876, HiC2877

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Functional Safety KFD2-ELD-(Ex)16
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:
•Presentdocument
• 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 functional safety products from Pepperl+Fuchs 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-ELD-(Ex)16

Functional Safety KFD2-ELD-(Ex)16
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-ELD-(Ex)16
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-ELD-(Ex)16
Product Description
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2ProductDescription
2.1 Function
General
The device detects ground faults on field lines.
The 16 channels of the device continuously monitor galvanically isolated circuits
and warns if their resistance to ground falls below 10 k.
During an alarm condition, the appropriate channel LED is illuminated and the
change-over contact is initiated (S1 = position I). The function of this relay can be
reversed with switch S1 (S1 = position II).
A self-test can be activated via the test input of the device. The device reacts by
switching the relay. The self-test can be triggered manually by the user or
remotely by the control system.
A fault is signalized by LEDs and a separate collective error message output.
If the device is operated via Power Rail, additionally a collective error message is
available.
The device is mounted on a 35 mm DIN mounting rail according to EN 60715.
KFD2-ELD-16
This signal conditioner provides the galvanic isolation between field circuits and
control circuits.
KFD2-ELD-Ex16
This isolated barrier is used for intrinsic safety applications.
2.2 Interfaces
The device has the following interfaces:
• Safety relevant interfaces: inputs 1 to 16
• Non-safety relevant interfaces: outputs 1 to 16 and supply
Note!
For corresponding connections see datasheet.
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Functional Safety KFD2-ELD-(Ex)16
Product Description
2.3 Marking
2.4 Standards and Directives for Functional Safety
Device-specific standards and directives
System-specific standards and directives
Pepperl+Fuchs GmbH
Lilienthalstraße 200, 68307 Mannheim, Germany
Internet: www.pepperl-fuchs.com
KFD2-ELD-16, KFD2-ELD-Ex16
Functional safety IEC/EN 61508, part 2, edition 2010:
Functional safety of
electrical/electronic/programmable electronic
safety-related systems (manufacturer)
Functional safety IEC/EN 61511, part 1 –3, edition 2003:
Functional safety –Safety instrumented systems for the
process industry sector (user)

Functional Safety KFD2-ELD-(Ex)16
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:
•thePFD
avg
value (average Probability of dangerous Failure on Demand) and
the T
1
value (proof test interval that has a direct impact on the PFD
avg
value)
•theSFFvalue(Safe Failure Fraction)
•theHFTarchitecture(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:
•thePFHvalue(Probability of dangerous Failure per Hour)
• Fault reaction time of the safety system
•theSFFvalue(Safe Failure Fraction)
•theHFTarchitecture(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.
Functional Safety KFD2-ELD-(Ex)16

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Functional Safety KFD2-ELD-(Ex)16
Planning
3.2 Assumptions
The following assumptions have been made during the FMEDA:
• Failure rate based on the Siemens standard SN29500.
• Failure rates are constant, wear is not considered.
• External power supply failure rates are not included.
• The device will be used under average industrial ambient conditions, which
are comparable with the classification "stationary mounted" in MIL-HDBK-
217F. Alternatively, the following ambient conditions are assumed:
• IEC/EN 60654-1 Class C (sheltered location) with temperature limits in the
range of the manufacturer's specifications and an average temperature of
40 ºC over a long period. The humidity level is within manufacturer's rating.
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.
3.3 Safety Function and Safe State
The device itself does not have a safety function. But in the case of failure, the
device can influence a connected safety loop.
The device can be used in conjunction with safety loops up to SIL 3. For the
SFF calculation, the failure rate of the device is added to the failure rate of the
safety loop. See chapter 3.4
3.4 Characteristic Safety Values
If a safety loop contains a KFD2-ELD-(Ex)16 device, the values of the device
must be added to the values of this safety loop.
The configuration of the device has no influence on the safety characteristic
values. There are no further failures that have a negative effect on the connected
safety loop.
Parameters acc. to IEC 61508 Characteristic values

du
0.002 FIT
PFH 2 x 10
-12
1/h
PFD
avg
for T
1
= 1 year 8.76 x 10
-9
Table 3.1

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Planning
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3.5 Useful Life Time
Although a constant failure rate is assumed by the probabilistic estimation this
only applies provided that the useful lifetime of components is not exceeded.
Beyond this useful lifetime, the result of the probabilistic estimation is
meaningless as the probability of failure significantly increases with time. The
useful lifetime is highly dependent on the component itself and its operating
conditions –temperature in particular. For example, the electrolytic capacitors
can be very sensitive to the operating temperature.
This assumption of a constant failure rate is based on the bathtub curve, which
shows the typical behavior for electronic components.
Therefore it is obvious that failure calculation is only valid for components that
have this constant domain and that the validity of the calculation is limited to the
useful lifetime of each component.
It is assumed that early failures are detected to a huge percentage during the
installation and therefore the assumption of a constant failure rate during the
useful lifetime is valid.
However, according to IEC/EN 61508-2, a useful lifetime, based on general
experience, should be assumed. Experience has shown that the useful lifetime
often lies within a range period of about 8 to 12 years.
As noted in DIN EN 61508-2:2011 note N3, appropriate measures taken by the
manufacturer and plant operator can extend the useful lifetime.
Our experience has shown that the useful lifetime of a Pepperl+Fuchs product
can be higher if the ambient conditions support a long life time, for example if the
ambient temperature is significantly below 60 °C.
Please note that the useful lifetime refers to the (constant) failure rate of the
device. The effective life time can be higher.

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Functional Safety KFD2-ELD-(Ex)16
Mounting and Installation
4 Mounting and Installation
Installing the Device
1. Observe the safety instructions in the instruction manual.
2. Observe the information in the manual.
3. Observe the requirements for the safety loop.
4. Connect the device only to devices that are suitable for this safety application.
5. Check the safety function to ensure the expected output behavior.
4.1 Configuration
Configuring the Device
The device is configured via DIP switches. The DIP switches are on the front of
the device.
1. De-energize the device before configuring the device.
2. Open the cover.
3. Configure the device via the DIP switches.
4. Close the cover.
5. Secure the DIP switches to prevent unintentional adjustments.
6. Connect the device again.
Note!
The device configuration via DIP switches is not safety relevant.
Note!
See corresponding datasheets for further information.
Functional Safety KFD2-ELD-(Ex)16

Functional Safety KFD2-ELD-(Ex)16
Operation
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5Operation
Operating the device
1. Observe the safety instruction in the instruction manual.
2. Observe the information in the manual.
3. Use the device only with devices that are suitable for this safety application.
4. Correct any occurring safe failures within 24 hours. Take measures to
maintain the safety function while the device is being repaired.
5.1 Proof Test Procedure
According to IEC/EN 61508-2 a recurring proof test shall be undertaken to reveal
potential dangerous failures that are not detected otherwise.
Check the function of the subsystem at periodic intervals depending on the
applied PFD
avg
in accordance with the characteristic safety values. 
See chapter 3.4.
It is under the responsibility of the plant operator to define the type of proof test
and the interval time period.
In the proof test, ensure that the impedance between the inputs is sufficiently low
to not endanger the safety relevant accuracy of the signal transfer.
Danger!
Danger to life from missing safety function
If the safety loop is put out of service, the safety function is no longer guaranteed.
• Do not deactivate the device.
• Do not bypass the safety function.
• Do not repair, modify, or manipulate the device.
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Functional Safety KFD2-ELD-(Ex)16
Maintenance and Repair
6 Maintenance and Repair
Maintaining, Repairing or Replacing the Device
In case of maintenance, repair or replacement of the device, proceed as follows:
1. Implement appropriate maintenance procedures for regular maintenance of
the safety loop.
2. Ensure the proper function of the safety loop, while the device is maintained,
repaired or replaced.
If the safety loop does not work without the device, shut down the application.
Do not restart the application without taking proper precautions.
Secure the application against accidental restart.
3. Do not repair a defective device. A defective device must only be repaired by
the manufacturer.
4. Replace a defective device only by a device of the same type.
Danger!
Danger to life from missing safety function
If the safety loop is put out of service, the safety function is no longer guaranteed.
• Do not deactivate the device.
• Do not bypass the safety function.
• Do not repair, modify, or manipulate the device.
Functional Safety KFD2-ELD-(Ex)16

Functional Safety KFD2-ELD-(Ex)16
List of Abbreviations
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7 List of Abbreviations
ESD Emergency Shutdown
FIT Failure In Time in 10
-9
1/h
FMEDA Failure Mode, Effects, and Diagnostics Analysis

s
Probability of safe failure

dd
Probability of dangerous detected failure

du
Probability of dangerous undetected failure

no effect
Probability of failures of components in the safety loop that have
no effect on the safety function. The no effect failure is not used
for calculation of SFF.

not part
Probability of failure of components that are not in the safety loop

total (safety function)
Safety function
HFT Hardware Fault Tolerance
MTBF Mean Time Between Failures
MTTR Mean Time To Restoration
PCS Process Control System
PFD
avg
Average Probability of dangerous Failure on Demand
PFH Average frequency of dangerous failure
PTC Proof Test Coverage
SFF Safe Failure Fraction
SIF Safety Instrumented Function
SIL Safety Integrity Level
SIL (SC) Safety Integrity Level (Systematic Capability)
SIS Safety Instrumented System
T
1
Proof Test Interval
FLT Fault
LB Lead Breakage
LFD Line Fault Detection
SC Short Circuit
Functional Safety KFD2-ELD-(Ex)16

Subject to modifications
Copyright PEPPERL+FUCHS • Printed in Germany
www.pepperl-fuchs.com
PROCESS AUTOMATION –
PROTECTING YOUR PROCESS
Worldwide Headquarters
Pepperl+Fuchs GmbH
68307 Mannheim · Germany
Tel. [phone]
E-mail: [email protected]
For the Pepperl+Fuchs representative
closest to you check www.pepperl-fuchs.com/contact
DOCT-5862
09/2017