background image

 2

018-

03

10

Functional Safety KFD2-VR4-Ex1.26

Planning

3.3

Safety Function and Safe State

Safety Function

The safety function of the device is fulfilled, as long as the output repeats the input voltage 

(0 V ... -20 V) with a tolerance of 

±

2 %.

Safe State

The safe state is defined, as the output being de-energized.

Reaction Time

The time that is needed to transfer a signal from the input of the device to the output according 

to the safety function.

Note!

See corresponding datasheets for further information.

Summary of Contents for KFD2-VR4-Ex1.26

Page 1: ...ISO9001 2 Functional Safety Voltage Repeater KFD2 VR4 Ex1 26 PROCESS AUTOMATION MANUAL...

Page 2: ...livery 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 rece...

Page 3: ...n 7 2 2 Interfaces 7 2 3 Marking 7 2 4 Standards and Directives for Functional Safety 7 3 Planning 8 3 1 System Structure 8 3 2 Assumptions 9 3 3 Safety Function and Safe State 10 3 4 Characteristic S...

Page 4: ...ting 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 app...

Page 5: ...nd 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 abso...

Page 6: ...e 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 sym...

Page 7: ...3 wire sensors 2 2 Interfaces The device has the following interfaces Safety relevant interfaces input output Non safety relevant interfaces power supply 2 3 Marking 2 4 Standards and Directives for F...

Page 8: ...e 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 t...

Page 9: ...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 1 5 x 10 3 For a SIL 2 application operating in high...

Page 10: ...lled as long as the output repeats the input voltage 0 V 20 V with a tolerance of 2 Safe State The safe state is defined as the output being de energized Reaction Time The time that is needed to trans...

Page 11: ...mode HFT 0 SIL hardware 2 sd su 1 1 Failures in components that are part of the safety function but do not influence the safety function are regarded as safe undetected 338 FIT dd 0 FIT du 103 FIT tot...

Page 12: ...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 percenta...

Page 13: ...nstructions 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 appl...

Page 14: ...he proof test interval The proof test detects dangerous undetected failures that can affect the safety function of the plant It is under the responsibility of the plant operator to define the type of...

Page 15: ...r the test 10 Restore the safety loop Proof Test Procedure B 1 Prepare the test set up see next figure 2 Connect an input load of 2 1 k to terminals 4 and 5 3 Connect an output load of 10 k to termina...

Page 16: ...VR4 Ex1 26 Operation Figure 5 1 Set up for proof tests A and B Zone 0 1 2 Div 1 2 Zone 2 Div 2 Multimeter V 4 6 2 3 1 5 KFD2 VR4 Ex1 26 7 8 24V DC 11 12 Power Rail 24VDC Input load 2 1 k Output load...

Page 17: ...across the resistor and the current derived from it The current value must be between 4 9 mA and 5 7 mA 4 Disconnect the ancillary equipment 5 Set back the device to the original settings after the te...

Page 18: ...across the resistor and the current derived from it The current value must be between 2 9 mA and 4 3 mA 4 Disconnect the ancillary equipment 5 Set back the device to the original settings after the te...

Page 19: ...aced 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...

Page 20: ...sed 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 Hard...

Page 21: ...Functional Safety KFD2 VR4 Ex1 26 Notes 2018 03 21...

Page 22: ...rl fuchs com Worldwide Headquarters Pepperl Fuchs GmbH 68307 Mannheim Germany Tel 49 621 776 0 E mail info de pepperl fuchs com For the Pepperl Fuchs representative closest to you check www pepperl fu...

Reviews: