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SAFETY PRECAUTIONS
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(Always read these instructions before using this equipment.)
Before using this product, please read this manual and the relevant manuals introduced in this manual
carefully and pay full attention to safety to handle the product correctly.
The instructions given in this manual are concerned with this product. For the safety instructions of the
programmable controller system, please read the User's Manual of the CPU module to use.
In this manual, the safety instructions are ranked as "DANGER" and "CAUTION".
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DANGER
CAUTION
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Indicates that incorrect handling may cause hazardous conditions,
resulting in death or severe injury.
Indicates that incorrect handling may cause hazardous conditions,
resulting in medium or slight personal injury or physical damage.
Note that the
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CAUTION level may lead to a serious consequence according to the circumstances.
Always follow the instructions of both levels because they are important to personal safety.
Please save this manual to make it accessible when required and always forward it to the end user.
[DESIGN PRECAUTIONS]
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DANGER
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If a communications error occurs to a device network, the node in such a communications error
will be in a state as follows:
(1) The master node (QJ71DN91) maintains input data which had been received from the slave
node before the error occurred.
(2) Whether the slave node's output signal is turned off or maintained is determined by the
slave node's specifications or the parameters set at the master node. When using
QJ71DN91 as a slave node, the entered data from master node before the faulty node is
maintained.
By referring to communications states of the slave node, arrange an interlock circuit in a
sequential program and provide safety mechanism externally of the slave node in order the
system to operate safely.
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CAUTION
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Do not bunch the control wires or communication cables with the main circuit or power wires, or
install them close to each other.
They should be installed 300 mm (11.8 inch) or more from each other. Not doing so could result
in noise that may cause malfunction.