Omron CJ-Series Operation Manual page 15

Application Precautions
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with the FALS(007) instruction, all outputs from Output Unit will be turned
OFF and only the internal output status will be maintained.)
• The contents of the DM, EM, and HR Areas in the CPU Unit are backed
up by a Battery. If the Battery voltage drops, this data may be lost. Provide
countermeasures in the program using the Battery Error Flag (A40204) to
re-initialize data or take other actions if the Battery voltage drops.
• Do not turn OFF the power supply to the PLC when data is being trans-
ferred. In particular, do not turn OFF the power supply when reading or
writing a Memory Card. Also, do not remove the Memory Card when the
BUSY indicator is lit. To remove a Memory Card, first press the memory
card power supply switch and then wait for the BUSY indicator to go out
before removing the Memory Card.
The Memory Card may become unusable if the power supply is turned
OFF or the Card is removed while data is being transferred.
• Confirm that no adverse effect will occur in the system before attempting
any of the following. Not doing so may result in an unexpected operation.
• Changing the operating mode of the PLC.
• Force-setting/force-resetting any bit in memory.
• Changing the present value of any word or any set value in memory.
• Install external safety measures against short-circuiting such as circuit
breakers in external wiring. Insufficient safety measures against short-cir-
cuiting may result in burning.
• 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.
• Mount Units only after checking terminal blocks and connectors com-
pletely.
• Before touching a Unit, be sure to first touch a grounded metallic object in
order to discharge any static build-up. Not doing so may result in malfunc-
tion or damage.
• Be sure that the terminal blocks, Memory Units, expansion cables, and
other items with locking devices are properly locked into place. Improper
locking may result in malfunction.
• Wire all connections correctly.
• 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.
• 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.
• Do not apply voltages to the Input Units in excess of the rated input volt-
age. Excess voltages may result in burning.
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