Omron CJ Series Operation Manual page 18

Application Precautions
• Fail-safe measures must be taken by the customer to ensure safety in the
event that outputs from Output Units remain ON as a result of internal cir-
cuit failures, which can occur in relays, transistors, and other elements.
• Fail-safe measures must be taken by the customer to ensure safety in the
event of incorrect, missing, or abnormal signals caused by broken signal
lines, momentary power interruptions, or other causes.
• Interlock circuits, limit circuits, and similar safety measures in external cir-
cuits (i.e., not in the Programmable Controller) must be provided by the
customer.
• Do not turn OFF the power supply to the PLC when data is being trans-
ferred.
• If the I/O Hold Bit is turned ON, the outputs from the PLC will not be
turned OFF and will maintain their previous status when the PLC is
switched from RUN or MONITOR mode to PROGRAM mode. Make sure
that the external loads will not produce dangerous conditions when this
occurs. (When operation stops for a fatal error, including those produced
with the FALS(007) instruction, all outputs from Output Unit will be turned
OFF and only the internal output status will be maintained.)
• Always use the power supply voltages specified in the operation manuals.
An incorrect voltage may result in malfunction or burning.
• Take appropriate measures to ensure that the specified power with the
rated voltage and frequency is supplied. Be particularly careful in places
where the power supply is unstable. An incorrect power supply may result
in malfunction.
• Install external breakers and take other safety measures against short-cir-
cuiting in external wiring. Insufficient safety measures against short-cir-
cuiting may result in burning.
• Separate the Temperature Control Unit from devices that generate short
harmonics.
• Always be sure that the power supply voltage and loads are within specifi-
cations and ratings.
• Disconnect the LG terminal on the Power Supply Unit from the GR termi-
nal when performing withstand voltage tests or insulation resistance tests.
Not disconnecting the functional ground terminal may result in burning.
• Install the Units properly as specified in the operation manuals. Improper
installation of the Units may result in malfunction.
• Be sure that all the terminal screws, and cable connector screws are tight-
ened to the torque specified in the relevant manuals. Incorrect tightening
torque may result in malfunction.
• Leave the label attached to the Unit when wiring. Removing the label may
result in malfunction if foreign matter enters the Unit.
• Remove the label after the completion of wiring to ensure proper heat dis-
sipation. Leaving the label attached may result in malfunction.
• Use crimp terminals for wiring. Do not connect bare stranded wires
directly to terminals. Connection of bare stranded wires may result in
burning.
• Wire all connections correctly as specified in this manual.
• Check the polarity before wiring terminals.
• Double-check all wiring and switch settings before turning ON the power
supply. Incorrect wiring may result in burning.
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