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[DESIGN PRECAUTIONS]
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DANGER
• When a communication error occurs on PROFIBUS-DP, the status of the faulty station is as
follows. Configure an interlock circuit in t he sequence program using the communication status
information (input X1) so that the system can operate safely.
Erroneous outputs and mis-operation could cause accidents.
(1) The input data from the master station remains unchanged from the data prior to the
communication error.
(2) When the master station becomes faulty, th e output status of the QJ71PB93D will be as in
the parameter settings of the master station.
(3) When any QJ71PB93D is down, the output state of other slave stations will be in
accordance with the parameter settings of the master station.
• Do not output (turn on) the "Use prohibited" signa l as the output signal to an intelligent function
module from the CPU module.
Writing data into the "system area" or outputting a signal for "Use prohibited" may cause system
malfunction in the programmable controller.

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CAUTION
• When the PROFIBUS cable is laid, do not lay it close to main circuits or power lines