Presentation about Functional Safety in mobile machinery and how this can be implemented by using the latest state of the art solution from Parker. A short overview is given about standards used for implementing safety functions. The presentation contains a technical description of the IQAN-MC4xFS solution and how these mobile controllers are capable of implementing safety functions in applications requiring IEC 61508 SIL2 / EN ISO 13849-1 PLd and how inputs and outputs can be used to meet design targets.
For more details: http://solutions.parker.com/IQAN-MC4xFS
How to Implement Functional Safety in Mobile Machinery IQAN MC4xFS Parker Hannifin
1. Achieving functional safety without compromising
performance with IQAN-MC4xFS controllers
How to implement Functional Safety
in Mobile Machinery
Gustav Widén
Systems Engineer Electronics
2. Mobile Applications requiring functional safety
Application Application safety standard
• Aerial platform EN 280
• Refuse rear loader EN 1501-1
• Refuse side loader EN 1501-2
• Refuse front loader EN 1501-3
• Refuse bin lift EN 1501-4
• Steer-by-wire ISO 5010
• Reach stacker LLMC EN 15000
• Lift truck EN 1175-2
• Loader crane EN 12999
• Telehandler LLMC EN 15000
• Forestry machinery EN ISO 11850
• Construction machinery EN 474-1, ISO 15998
• …
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3. CE marking of machinery
EN ISO 13849-1 Safety of machinery
– Safety-related parts of control systems
Harmonized standard used by machine manufacturers to
prove that machinery meets the Directive requirements
on safety and reliability of control systems
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- control system aspects
Machinery Directive EMC directive ROHS II Low Voltage Directive
Safety and reliability of control systems
4. The Machinery directive states:
Safety and reliability of control systems
– Control systems must be designed and constructed in such a way as to prevent
hazardous situations from arising. Above all, they must be designed and
constructed in such a way that:
• they can withstand the intended operating stresses and external
influences,
• a fault in the hardware or the software of the control system does not
lead to hazardous situations,
• errors in the control system logic do not lead to hazardous situations,
• reasonably foreseeable human error during operation does not lead to
hazardous situations.
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Directive 2006/42/EC, Annex 1, clause 1.2.1.
5. State of the art is evolving
The Machinery Directive* states:
(14) The essential health and safety requirements should be
satisfied in order that machinery is safe; these requirements
should be applied with discernment to take account of the
state of the art at the time of construction and of technical and
economic requirements.
Mobile machinery application specific standards evolve; with increased level of detail
on control system requirements. Most include reference to EN 13849-1 Performance
Levels on specific safety functions.
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6. IQAN-MC4xFS
For applications requring IEC 61508 SIL2 / EN ISO
13849-1 PLd
– Used where safety relies on de-energizing the coils
on hydraulic valves
– Normal functions and safety functions can be
implemented in the same module
Scalable design
– MC41FS for one or two safety functions
– MC42FS higher number of safe outputs
– MC43FS large centralized controller for several
safety functions
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8. Structure of a safety function
Input subsystem Logic subsystem Output subsystem
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IQAN-MC43
9. Examples of safety functions
• Examples from EN ISO 13849-1
– start/restart function
– hold-to-run function
– enabling device function
– control modes and mode selection
– Emergency stop function (complimentary protective measure).
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10. Standards used for implementing
safety functions
• IEC 61508
– Used in different industries, including machinery
– High focus on development process and detailed analysis
– Well suited for developing subsystems with complex electronics and embedded
software
• EN ISO 13849-1
– Specific to machinery
– High focus on hardware architecture, allows for estimates on diagnostics, covers
also hydraulics, somewhat limited in requirements on software
– Can bring in IEC 61508 subsystems as safety related parts
– Well suited for complete safety function
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11. IEC 61508
• The gold standard for functional safety in
electrical, electronic and programmmable
electronic systems
– Foundation for other application area
international standards
• Safety integrity levels, SIL 1 to SIL 4
– Hardware safety integrity, quantifying
effect of random failures (PFHd)
• Robust components, architecture,
hardware diagnostics
– Systematic capability
• Development process, software
design, EMI, ..
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12. EN ISO 13849-1
• For functional safety in machinery, applicable to electrical, programmable
electronic, hydraulic, pneumatic and mechanical.
– Referenced by mobile machinery C-standards, often specifying safety functions
with PL c and PL d.
• Performance Level (PL) Levels PL a to PL e, evaluated based on:
– Quantifiable aspect of PL, hardware reliability modelling based on
• Architecture (categories B, 1, 2, 3 or 4)
• MTTFd of components
• Diagnostics (DC)
• Common cause failures (CCF)
– Non-quantifiable aspects
• Safety related software (SRASW, SRESW)
• Avoidance of systematic faults
• Environmental robustness
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13. EN ISO 13849-1:2015
Solutions depending on required PL
EN 13849-1 PL IEC 61508 SIL EN 13849-1 hardware electronics EN 13849-1 safety related
embedded SW
a - Basic safety principles (category B) Basic requirements only
b 1 MTTFd on controllers and sensors Basic requirements only
c 1
Category 2 or 3, MTTFd, DC, CCF
or
IEC 61508 SIL 1
EN 13849-1 4.6.2
or
IEC 61508 SIL 1
d 2
Category 2 or 3, MTTFd, DC, CCF
or
IEC 61508 SIL 2
EN 13849-1 4.6.2
or
IEC 61508 SIL 2
e 3
Category 3 or 4, MTTFd, DC, CCF
or
IEC 61508 SIL 3
IEC 61508-3 SIL 3
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14. EN 13849-1
Combining safety related parts of control
system (subsystems)
Sensors initiating safety
function
Evaluate with EN 13849-1
• Combine two
redundant sensors to
Category 3
• Component MTTFd
from datasheet (e.g.
IQAN-SP500)
• Evaluate DC and CCF
• Calculate PL =
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Logic unit
Already certified
to
IEC 61508 SIL2
PL = PL d
Directional valve
Evaluate with EN
13849-1
Reliable non-complex
Category 1
PL = PL c
S2
S1
V1
IQAN-MC43FS
15. EN ISO 13849-1
Overview of PL for safety function
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MTTFd MTTFd of
each channel
DCavg
DC
Category
CCF >65
PL (quantifiable)
PFHd
PL (quantifiable)
Systematic
Environmental
Software
PL for subsystems
PL
for safety function
Σ PFHd
16. Complete safety function, calculate
combined PFHd
Probability of dangerous failure per hour
The IQAN-MC4xFS gives margins to
complete safety function
IQAN-MC41FS 7.63 x10-8
IQAN-MC42FS 7.92 x10-8
IQAN-MC43FS 9.29 x10-8
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< 1x10-5
< 1x10-6
< 1x10-7
< 3x10-6
SIL1, PLb
SIL1, PLc
SIL2, PLd
17. IQAN-MC4xFS, hardware and embedded software
Inputs
•Monitoring of VREF
•Monitoring of ADC
•Monitoring of pulse inputs
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Outputs
•Monitoring of power drivers
•Monitoring of wiring
Core
Hardware diagnostics
Correct execution of software
Application, created in IQANdesign
Inputs
Use inputs in pair
Cross monitor sensors
Functionality
Correct application logic
Outputs
Use safe outputs
Control hydraulics
18. IQAN-MC4xFS
Key features for functional safety
• Lockstep MCU
• Safety related application executed in lockstep core
• ECC protected Flash and RAM
• Checksums on settings (FRAM)
• Independent safety power supply
• Monitoring of all voltages and critical temperatures
• Using IEC 61508 SIL3 safety certified real-time OS
• Isolation using MMU
• Running IQAN application interpreter (vmAC)
• Automatic error detecton and action on COUT/DOUT
• Built to withstand the harsh environment on mobile
machinery
• Meets and exceeds EMI requirements for mobile machinery
• Development process in accordance with IEC 61508:2010
• IEC 61508 functional safety assessment and certification by
RISE
• 2006/42 EC type examination by RISE as logic unit to ensure
safety functions
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19. IQAN
Data driven system
IQAN is an interpreting system
• Called data-driven system with IEC 61508
terminology
• All embedded software is built and tested by Parker
before each release.
• IQANdesign users focus on the application, without
running the risk of creating anything that access the
wrong parts
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Application
Application
interpreter
Drivers
RTOS
Application
Settings
vmAC
Design Project/clone file Target controller
20. IQAN-MC43FS inputs
50 input pins
• 26 analog inputs use for 0-5V or as digital input
• 2 analog inputs for 0-32V
• 4 current loop inputs for 4-20mA signals
• 6 timer inputs frequency, pulse or digital inputs
• 12 digital inputs dedicated
All possible to use in safety functions
• Any input pin may be used as part of a safety
functions
• Normal input usage is in pairs for redundant
sensors
– IQANdesign compare channels recommended
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21. Analog inputs on MC4xFS
• VIN, Voltage input 0.5-4.5V
– Dual crossed signals recommended for diagnostics on both sensor and
inputs
– Internal monitoring of AD Converter and reference:
• Single signal or dual identical signals possible with wider
margins on safe failure 10%
– Range limit in application required
• CIN, Current loop input 4-20mA
– Dual crossed signals recommended for diagnostics on both sensor and
inputs
– Internal monitoring of AD Converter and reference:
• Single signal or dual identical signals possible with wider
margins on safe failure 10%
– Range limit in application required
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Raw value
[mV]
22. Frequency type inputs on
MC4xFS
Each frequency inputs is connected to two separate processor input ports
• PWMIN, PWM input 5%-95% MR
– Dual signals recommended for diagnostics on both sensor and inputs
– Input monitoring of MR range and frequency
• Single signal possible
– Range limit in application required
• FIN, PCNT, DFIN, DPCNT, Frequency/pulse inputs 0-50 kHz
– Dual signals required for diagnostics on both sensor and inputs
– Use IQANdesign compare channel
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23. Digital inputs on MC4xFS
• DIN, on-off input with pull-up or pull-down
– Dual signals are always required for DIN
– Use IQANdesign Digital Compare channel
– Dual antivalent signals recommended for best
diagnostics on both sensor and inputs
– Dual identical signal possible, application must
consider if sensor diagnostics is reduced
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High
Low
Dual opposite signals
High
Low
Dual identical signals
24. IQAN-MC43FS outputs
46 output pins
• 10 COUT for CAM precision control of up to 10
directional proportional valves, pins combine
with
• 20 power low side used in COUT or Digital out
HS+LS for up to 2.5A
• 8 DOUT/PWM high side driver up to 4 A
• 8 low current low side for LED lamp control (non
safety related)
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25. IQAN COUT
Motion control made easy with Parker Hannifin's
CAM regulator for proportional control of mobile
pumps and valves based on 30+ years of
experience.
CAM - Parker Hannifin solution for precision
control of proportional mobile pumps and valves
• No tuning or tweaking CAM regulator circuit
guaranties consistent performance
• Precision control with a resolution down to 1
mA, a must when there is need for controlling
hydrostatic transmissions or precise crane
movements
• Zero drift control provide the lowest possible
output offset current and drift. Parker Hannifin's
zero drift CAM offer initial offset current of less
than 5mA and almost immeasurable offset
current drift over time, temperature and load
change
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26. MC4xFS output connections
for safety functions
COUT, bidirectional
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COUT, single coil DOUT HS +LS
100-2500 mA 100-2500 mA 60-2500 mA
27. Other output connections
Not for safety related machine control
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PWM out HS
DOUT HS
DOUT HS +LS,
multiple low side
DOUT LS
low current (MC43)
≤ 4000 mA 60-2500 mA ≤ 300 mA
28. MC43FS outputs
• Combination of high-side and low
side switches for handling also
external wiring faults
• On FS versions, each DOUT HS+LS
has exactly one highside switch per
coil.
• Each unused DOUT HS+LS
combination can make one more
COUT bidirectional and leave one
DOUT HS for non safety related
functions
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5 COUT bidirectional
(safe)
5 DOUT HS+LS
(safe)
3 DOUT HS, for non
safety related functions
29. Advantages of using IQAN
for functional safety
• Safety certification on IQAN design tool for development
– No compilation of application or embedded software, all embedded SW and the IQAN application
interpreter is compiled and verified by Parker
– Highlight and document safety functions, guided by project check
– Built-in well defined and secure interface if IQAN master display is used for tuning of a safety related
parameter, limits and security handled by safety master.
– Design tool that is specific to the needs of mobile machinery, easy to create the intended function
– Predictable real-time performance
• Safety certification on IQANrun for SW download and parametrization
– Security level for tuning/calibration of any safety related parameters
• Simulation in IQANsimulate helps when checking the application software, before verification even begins.
Bottom line
– Enables the machine designer to focus on machine functionality and safety
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31. WARNING — USER RESPONSIBILITY
FAILURE OR IMPROPER SELECTION OR IMPROPER USE OF THE PRODUCTS DESCRIBED HEREIN OR RELATED
ITEMS CAN CAUSE DEATH, PERSONAL INJURY AND PROPERTY DAMAGE.
This document and other information from Parker-Hannifin Corporation, its subsidiaries and authorized
distributors provide product or system options for further investigation by users having technical expertise.
The user, through its own analysis and testing, is solely responsible for making the final selection of the
system and components and assuring that all performance, endurance, maintenance, safety and warning
requirements of the application are met. The user must analyze all aspects of the application, follow
applicable industry standards, and follow the information concerning the product in the current product
catalog and in any other materials provided from Parker or its subsidiaries or authorized distributors.
To the extent that Parker or its subsidiaries or authorized distributors provide component or system options
based upon data or specifications provided by the user, the user is responsible for determining that such data
and specifications are suitable and sufficient for all applications and reasonably foreseeable uses of the
components or systems.
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32. Gustav Widén
Systems Engineer Electronics
Parker Hannifin Manufacturing Sweden AB
Box 222 (Mölnlycke Fabriker 14) · 435 25 Mölnlycke
Sweden
More information here: IQAN-MC4xFS
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