Parker iqan-mc3, Руководство пользователя

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7
Safety concept
4 Safety
Instruction book, IQAN-MC3
4 Safety
Safety concept
All IQAN modules are designed for controlling hydraulic implements on mobile
machines, and when basic safety principles are observed, they can be used for normal
functions.
The IQAN-MC3 is designed in accordance with IEC 61508, for use in applications
with higher demands on functional safety. When there is a need to prove the safety
integrity of each implemented safety function, the unit can be used for functions with a
maximum safety integrity of SIL2.
Safe state
The safety analysis of the IQAN-MC3 is done under the assumption that the system is
in a safe state when the controller is off.
W
ARNING
System design must not allow any unintentional movement when the unit is off.
If any critical fault within the IQAN-MC3 is detected by its internal checks, the
controller will shut down all outputs, including CAN.
• If a fault on one output is detected, that output will be shut off.
• If this occurs, the stop ramps on on the outputs will have no effect, the outputs will
shut off immediately.
Therefore, the application must be designed so that a sudden stop on the outputs does
not in itself lead to a hazardous situation.
Maximum achievable SIL and PL
The IQAN-MC3 is designed for use in safety functions of up to SIL2 (IEC 61508).
The IQAN-MC3 in itself does not come with any safety function; it needs to be put into
a system and loaded with an application file.
It is recommended for the developer of the safety function to apply a standard written
specifically for machine manufacturers when designing safety functions with the
IQAN-MC3.
Suitable standards for machinery are EN ISO 13849-1, or IEC/EN 62061. The
following table shows the relationship between Performance Level (PL) and Safety
Integrity Level (SIL), and also the corresponding average probability of dangerous
failure per hour (PFHd).
The PL and SIL are based both on quantifiable aspects and on non-quantifiable aspects
such as the development process used and the safety related software.
MC3-SMR-003:A Safe state
The application shall be designed so that the system is in a safe state when the
controller is off.