Pepperl+Fuchs KFD0-CS 50 Series User manual

ISO9001
2
Functional Safety
Current Driver/Repeater
KFD0-CS-(Ex)*.50(P),
KFD0-CS-(Ex)*.51(P)*
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 KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)

Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Characteristic Safety Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.5 Useful Lifetime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4 Mounting and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.1 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.1 Proof Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6 Maintenance and Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7 List of Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

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Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Introduction
1Introduction
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 KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
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 KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
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 KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Product Description
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2 Product Description
2.1 Function
KFD0-CS-*.50
This signal conditioner provides the galvanic isolation between field circuits and control
circuits.
The device can be used as a repeater or transmitter power supply for 2-wire transmitters.
The device is loop powered. From the control side no additional power supply has
to be connected.
Use the technical data to verify that proper voltage is available to the field devices.
The device is mounted on a 35 mm DIN mounting rail according to EN 60715.
KFD0-CS-Ex*.50(P)
This isolated barrier is used for intrinsic safety applications.
The device can be used as a repeater or transmitter power supply for 2-wire transmitters.
The device is loop powered. From the control side no additional power supply has
to be connected.
Use the technical data to verify that proper voltage is available to the field devices.
The device is mounted on a 35 mm DIN mounting rail according to EN 60715.
P Version
A reverse polarity protection prevents damage to the device caused by faulty wiring.
KFD0-CS-*.51(P)
This signal conditioner provides the galvanic isolation between field circuits
and control circuits.
The device transfers DC signals of fire alarms and smoke alarms from the field side
to the control side. The device can also be used to control I/P converters, valves, indicators,
and audible alarms.
The device is loop powered. From the control side no additional power supply has
to be connected.
Use the technical data to verify that proper voltage is available to the field devices.
The device is mounted on a 35 mm DIN mounting rail according to EN 60715.
P Version
A reverse polarity protection prevents damage to the device caused by faulty wiring.

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Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Product Description
KFD0-CS-Ex*.51(P)
This isolated barrier is used for intrinsic safety applications.
The device transfers DC signals of fire alarms and smoke alarms from the hazardous area
to the non-hazardous area. The device can also be used to control I/P converters, valves,
indicators, and audible alarms.
The device is loop powered. From the control side no additional power supply has
to be connected.
Use the technical data to verify that proper voltage is available to the field devices.
The device is mounted on a 35 mm DIN mounting rail according to EN 60715.
P Version
A reverse polarity protection prevents damage to the device caused by faulty wiring.
2.2 Interfaces
The device has the following interfaces.
• Safety-relevant interfaces:
• 1-channel devices: input I, output I
• 2-channel devices: input I, input II, output I, output II
• Non-safety-relevant interfaces: none
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 GmbH
Lilienthalstraße 200, 68307 Mannheim, Germany
Internet: www.pepperl-fuchs.com
KFD0-CS-1.50, KFD0-CS-2.50, KFD0-CS-2.51P
KFD0-CS-Ex1.50P, KFD0-CS-Ex2.50P, KFD0-CS-Ex1.51P,
KFD0-CS-Ex2.51P
Up to SIL 2
Functional safety IEC/EN 61508, part 1 –7, 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 KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
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
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:
•thePFHvalue(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 KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Planning
3.2 Assumptions
The following assumptions have been made during the FMEDA:
• Failure rate based on the Siemens standard SN 29500.
• 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 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.
SIL 2-Application
• The device shall claim less than 10 % of the total failure budget for a SIL 2 safety loop.
• 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.
• For a SIL 2 application operating in high demand mode the total PFH value
of the SIF should be smaller than 10-6 per hour, hence the maximum allowable PFH value
would then be 10-7 per hour.
• The safety-related device is considered to be of type Adevice with a hardware fault
tolerance of 0.
• Since the safety loop has a hardware fault tolerance of 0and it is a type Adevice,
the SFF must be > 60 % according to table 2 of IEC/EN 61508-2 for a SIL 2 (sub) system.
3.3 Safety Function and Safe State
Safety Function
The device transfers current signals from the input to the output with a maximum tolerance
of 5 % related to the full signal range.
Safe State
In the safe state the output is < 3.6 mA.
Reaction Time
The reaction time for all safety functions is < 20 ms.
Note!
See corresponding datasheets for further information.

Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Planning
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3.4 Characteristic Safety Values
The characteristic safety values like PFD, SFF, HFT and T1are taken from
the SIL report/FMEDA report. Observe that PFD and T1are related to each other.
The function of the devices has to be checked within the proof test interval (T1).
Parameters Characteristic values
Assessment type and
documentation
Full assessment
Device type A
Mode of operation Low Demand Mode or High Demand Mode
HFT 0
SIL 2
SC 3
Safety function Current driver Repeater
s1
1No effect failures" are not influencing the safety function and are therefore not included in SFF and in the failure rates
of the safety function.
57 FIT 0 FIT
dd 0 FIT 62 FIT
du 24.9 FIT 22.8 FIT
total (safety function)182 FIT 85 FIT
not part 120 FIT 95 FIT
SFF 169 % 73 %
PTC 100 % 100 %
MTBF 2
2acc. to SN29500. This value includes failures which are not part of the safety function/MTTR = 8 h.
438 years 438 years
PFH 2.49 x 10-8 1/h 2.28 x 10-8 1/h
PFDavg for T1= 1 year 1.09 x 10-4 1.00 x 10-4
PFDavg for T1= 2 years 2.18 x 10-4 2.00 x 10-4
PFDavg for T1= 5 years 5.44 x 10-4 5.00 x 10-4
Reaction time 3
3Time between fault detection and fault reaction
< 20 ms
Table 3.1

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Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Planning
3.5 Useful Lifetime
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.

Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Mounting and Installation
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4 Mounting and Installation
Mounting and 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
A configuration of the device is not necessary and not possible.

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Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Operation
5Operation
Operating the device
1. Observe the safety instructions 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 8 hours. Take measures to maintain
the safety function while the device is being repaired.
5.1 Proof Test
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 PFDavg
in accordance with the characteristic safety values provided. 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.
With the following instructions a proof test can be performed which will reveal all
of the possible dangerous faults (diagnostic coverage 100 %).
Equipment required:
• Digital multimeter with an accuracy better than 0.1 %
Use for the proof test of the intrinsic safety side of the device a special digital multimeter
for intrinsically safe circuits.
Intrinsically safe circuits that were operated with non-intrinsically safe circuits may
not be used as intrinsically safe circuits afterwards.
• Variable power supply 0 V DC to 24 V DC
• Process calibrator with current source/sink function (mA) with an accuracy
better than 20 µA
• Load resistors 698 1%0.5W,1k1%,0.5W
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 KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Operation
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Proof Test for Current Source Connection
Proof Test Procedure
1. Disconnect the field circuit.
2. Check the device as shown in the following tables.
3. After check reset the device to the necessary settings.
4. Connect the field circuit again.
5. Check the correct behavior of the safety loop.
Figure 5.1 Proof test set-up for KFD0-CS-(Ex)*.5*(P) for current source connection
Channel 2 only for KFD0-CS-(Ex)2.5*(P).
Usage in Zone 0, 1, 2/Div. 1, 2 only for Ex versions.
Step
No.
Set supply
voltage (V)
Set load current
(mA)
Measurement point
Input current (mA)
all devices
Output voltage
(V) .50 devices
Output voltage
(V) .51 devices
14.00 0.00 0.00 ±0.20 n.a. 4.00 ±1.00
210.00 0.00 0.00 ±0.20 10.00 ±1.00 10.00 ±1.00
335.00 4.00 4.00 ±0.20 19.50 ±1.00 19.56 ±1.00
410.00 20.00 20.00 ±0.20 0.60 ±1.00 1.60 ±1.00
535.00 20.00 20.00 ±0.20 13.80 ±1.00 13.80 ±1.00
620.00 40.00 40.00 ±0.20 n.a. 2.20 ±1.00
Table 5.1 Steps to be performed for the proof test
Note!
For the polarity protected versions the measurement values never go below 0 V.
Where the output value is marked "n.a." this test is not applicable, In that case the current
measurement is not applicable as well.
KFD0-CS-Ex2.5*(P)
Zone 2
Div. 2
Zone 0, 1, 2
Div. 1, 2
2-
1+ 11+
12-
9+
10-
8-
5-
4+
I
II
mA
Multimeter
(V)
mA
Multimeter
(V)
V
V

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Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Operation
Proof Test for Load Resistor Connection
Proof Test Procedure
1. Disconnect the field circuit.
2. Connect a current supply. Supply the device with a voltage of 30 V.
3. Connect a a load resistor of 700 . Set the current source to 20 mA.
The output current must be 20.0 mA ±0.2 mA.
4. Connect a a load resistor of 1 k. Set the current source to 4 mA.
The output current must be 4.0 mA ±0.2 mA.
5. After check reset the device to the necessary settings.
6. Connect the field circuit again.
7. Check the correct behavior of the safety loop.
Figure 5.2 Proof test set-up for KFD0-CS-(Ex)*.5*(P)
Channel 2 only for KFD0-CS-(Ex)2.5*(P).
Usage in Zone 0, 1, 2/Div. 1, 2 only for Ex versions.
KFD0-CS-Ex2.5*(P)
Load
resistor
Load
resistor
Zone 2
Div. 2
Zone 0, 1, 2
Div. 1, 2
2-
1+ 11+
12-
V
9+
10-
8-
5-
4+
I
II
mA
Multimeter
(mA )
mA
Multimeter
(mA )
V

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Maintenance and Repair
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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. While the device is maintained, repaired or replaced, the safety function does not work.
Take appropriate measures to protect personnel and equipment while the safety function
is not available.
Secure the application against accidental restart.
3. Do not repair a defective device. A defective device must only be repaired by
the manufacturer.
4. If there is a defect, always replace the device with an original device.
Danger!
Danger to life from missing safety function
Changes to the device or a defect of the device can lead to device malfunction.
The function of the device and the safety function is no longer guaranteed.
Do not repair, modify, or manipulate the device.

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Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
List of Abbreviations
7 List of Abbreviations
ESD Emergency Shutdown
FIT Failure In Time in 10-9 1/h
FMEDA Failure Mode, Effects, and Diagnostics Analysis
sProbability 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) Probability of failure of components that are in the safety loop
HFT Hardware Fault Tolerance
MTBF Mean Time Between Failures
MTTR Mean Time To Restoration
PCS Process Control System
PFDavg Average Probability of dangerous Failure on Demand
PFH Average frequency of dangerous failure
PLC Programmable Logic Controller
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
T1Proof Test Interval

Functional Safety KFD0-CS-(Ex)*.50(P), KFD0-CS-(Ex)*.51(P)
Notes
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Subject to modifications
Copyright PEPPERL+FUCHS • Printed in Germany
www.pepperl-fuchs.com
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
PROCESS AUTOMATION –
PROTECTING YOUR PROCESS
DOCT-4073
12/2018