Safety Precautions - Mitsubishi Electric MELSEC-Q Series 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]
● For the operating status of each station after a communication failure in the data link, refer to Page
121, Section 7.5 in this manual. Failure to do so may result in an accident due to an incorrect output or
malfunction.
● When connecting a peripheral with the CPU module or connecting an external device, such as a
personal computer, with an intelligent function module to modify data of a running programmable
controller, configure an interlock circuit in the program to ensure that the entire system will always
operate safely. For other forms of control (such as program modification or operating status change)
of a running programmable controller, read the relevant manuals carefully and ensure that the
operation is safe before proceeding. Especially, when a remote programmable controller is controlled
by an external device, immediate action cannot be taken if a problem occurs in the programmable
controller due to a communication failure. To prevent this, configure an interlock circuit in the program,
and determine corrective actions to be taken between the external device and CPU module in case of
a communication failure.
● Do not write any data to the "system area" of the buffer memory in the intelligent function module.
Also, do not use any "use prohibited" signal as an output signal from the CPU module to the intelligent
function module. Doing so may cause malfunction of the programmable controller system.

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".
CAUTION" may lead to
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