Safety Precautions - Mitsubishi Electric QJ71DN91 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: "
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]
 If a communications error occurs on a DeviceNet network, faulty nodes will behave as follows:
(1) The master node (QJ71DN91) holds input data which had been received from slave nodes
before the error occurred.
(2) Whether output signals of a slave node are turned off or held is determined by the slave
node's specifications or the parameters set at the master node. When the QJ71DN91 is
used as a slave node, it holds data that have been input from the master node before the
communication error.
Utilizing communications states of slave nodes, create an interlock circuit on sequential
programs and provide safety mechanism externally so that the system will operate safely.
 Do not install control wires or communication cables together with the main circuit or power
wires, or bring them close to each other.
Keep a distance of 300mm or more between them.
Failure to do so may cause malfunctions due to noise.
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 SAFETY PRECAUTIONS 
(Read these precautions before using this product.)
WARNING
!
CAUTION
!
WARNING" and "
CAUTION" may lead to
CAUTION".
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