[DESIGN PRECAUTIONS]
!
WARNING
• 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.

!
CAUTION
• 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 300 mm (11.8 inch) or more between them.
Failure to do so may cause malfunctions due to noise.