Pepperl+Fuchs NCN3-F31K2 Series User manual

ISO9001
2
Functional Safety
Inductive Dual Sensor
NCN3-F31K2(M)-N*-B*3-S
FACTORY 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 NCN3-F31K2(M)-N*-B*3-S

Functional Safety NCN3-F31K2(M)-N*-B*3-S
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 Safe. . . . . . . . . . . . . . . . . . . . 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 Mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.3 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1 Proof Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6 Maintenance and Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7 List of Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

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Functional Safety NCN3-F31K2(M)-N*-B*3-S
Introduction
1 Introduction
1.1 Content of this Document
This document contains safety-relevant information for usage of the device.
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!
For full information on the product, refer to the further documentation on the Internet
at www.pepperl-fuchs.com.

Functional Safety NCN3-F31K2(M)-N*-B*3-S
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 NCN3-F31K2(M)-N*-B*3-S
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 NCN3-F31K2(M)-N*-B*3-S
Product Description
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2 Product Description
2.1 Function
General
The device is an inductive dual sensor. Dual sensors are used, for example, to detect the final
positions of valve positions in valve actuators.
Inductive dual sensors consist of 2 sensor circuits arranged one above the other.
Each sensor has its own coil. If a measuring plate is inside the sensing range of one
of the coils, the magnetic field of the coil is influenced and an electrical switching signal
is generated.
The device is a NAMUR sensor with 2 independent sensor circuits in 2-wire configuration.
The device transmits the binary signal according to NAMUR to a connected control unit.
A control unit can, e. g., be a switch amplifier or an I/O card in a PLC.
NCN3-F31K2(M)-N4-B*3-S
The sensor has two separate sensor circuits with NC function (normally-closed).
The device is in high impedance state when a measuring plate is located within the sensing
range of the respective sensor circuit.
The sensor has a rated operating distance sn of 3 mm.
NCN3-F31K2-N5-B*3-S
The sensor has two sensor circuits. One sensor circuit of these sensor circuits is activated
depending on the polarity of the supply voltage. The active sensor circuit is in high impedance
state when a measuring plate is located within the sensing range of this sensor circuit.
The sensor has a rated operating distance sn of 3 mm.
2.2 Interfaces
The device has the following interfaces.
• Safety relevant interface: device output
• Non-safety relevant interface: none
Note
See corresponding datasheets for further information.
Note
For corresponding connections see datasheet.

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Functional Safety NCN3-F31K2(M)-N*-B*3-S
Product Description
2.3 Marking
2.4 Standards and Directives for Functional Safe
Device-specific standards and directives
Pepperl+Fuchs Group
Lilienthalstraße 200, 68307 Mannheim, Germany
Internet: www.pepperl-fuchs.com
NCN3-F31K2-N4-B13-S
NCN3-F31K2-N4-B33-S
NCN3-F31K2M-N4-B13-S
NCN3-F31K2M-N4-B23-S
NCN3-F31K2-N5-B13-S
NCN3-F31K2-N5-B33-S
Up to SIL 2
Functional safety IEC/EN 61508, part 1 –2, edition 2010:
Functional safety of electrical/electronic/programmable electronic
safety-related systems (manufacturer)

Functional Safety NCN3-F31K2(M)-N*-B*3-S
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.

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Functional Safety NCN3-F31K2(M)-N*-B*3-S
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 safety-related device is considered to be of type A device with a hardware fault
tolerance of 0.
• 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
Only use the device in SIL 2 applications in combination with a control unit according
to EN 60947-5-6 (NAMUR).
• The device claims less than 25 % 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 1 x 10-2,
hence the maximum allowable PFDavg value would then be 2.5 x 10-3.
• For a SIL 2 application operating in high demand mode the total PFH value
of the SIF should be smaller than 1 x 10-6 per hour, hence the maximum allowable
PFH value would then be 2.5 x 10-7 per hour.
• Since the safety loop has a hardware fault tolerance of 0 and it is a type A device,
the SFF must be > 60 % according to table 2 of IEC/EN 61508-2 for a SIL 2 (sub) system.