Omron CJ Series Operation Manual page 25

Application
Do not touch any Unit when power is being supplied or immediately
after the power supply is turned OFF. Doing so may result in burn
injury.
Wiring
Be sure that all terminal screws and cable connector screws are
tightened to the torque specified in the relevant manuals. The loose
screws may result in fire or malfunction.
Online Editing
Execute online editing only after confirming that no adverse effects
will be caused by deviations in the timing of I/O. If you perform online
editing, the task execution time may exceed the task period, I/O may
not be refreshed with external devices, input signals may not be
read, and output timing may change.
CJ-series CompoNet Master Unit Operation Manual for NJ-series CPU Unit (Cat. No. W493)
Caution
Safety Precautions
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