Safety Precautions - Mitsubishi QX10 User Manual

Before using this product, please read this manual and the relevant manuals carefully and pay full
attention to safety to handle the product correctly.
The precautions given in this manual are concerned with this product only. For the safety precautions of
the programmable controller system, refer to the user's manual for the CPU module used.
In this manual, the safety precautions are classified into two levels: "
WARNING
!
CAUTION
!
Under some circumstances, failure to observe the precautions given under "
serious consequences.
Observe the precautions of both levels because they are important for personal and system safety.
Make sure that the end users read this manual and then keep the manual in a safe place for future
reference.
[Design Precautions]
• Configure safety circuits external to the programmable controller to ensure that the entire system
operates safely even when a fault occurs in the external power supply or the programmable
controller. Failure to do so may result in an accident due to an incorrect output or malfunction.
(1) Configure external safety circuits, such as an emergency stop circuit, protection circuit, and
protective interlock circuit for forward/reverse operation or upper/lower limit positioning.
(2) When the programmable controller detects an abnormal condition, it stops the operation and
all outputs are:
(a) Turned off if the overcurrent or overvoltage protection of the power supply module is
activated.
(b) Held or turned off according to the parameter setting if the self-diagnostic function of the
CPU module detects an error such as a watchdog timer error.
Note, however, that AnS series modules on the system turn off all outputs in both cases.
All outputs may turn on if an error occurs in a part, such as an I/O control part, where the
CPU module cannot detect any error. To ensure safety operation in such a case, provide a
safety mechanism or a fail-safe circuit external to the programmable controller. For a fail-
safe circuit example, refer to the user's manual for the CPU module used.
(3) Outputs may remain on or off due to a failure of an output module relay or transistor.
Configure an external circuit for monitoring output signals that could cause a serious
accident.
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 SAFETY PRECAUTIONS 
(Read these precautions before using this product.)
Indicates that incorrect handling may cause hazardous conditions,
resulting in death or severe injury.
Indicates that incorrect handling may cause hazardous conditions,
resulting in minor or moderate injury or property damage.
WARNING
!
WARNING" and "
! !
CAUTION" may lead to
!
CAUTION".
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