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Application Precautions
5
!Caution
The operating environment of the PLC System can have a large effect on the
longevity and reliability of the system. Improper operating environments can
lead to malfunction, failure, and other unforeseeable problems with the PLC
System. Be sure that the operating environment is within the specified condi-
tions at installation and remains within the specified conditions during the life
of the system.
5
Application Precautions
Observe the following precautions when using the CompoBus/S Units or the
PLC.
!WARNING
Failure to abide by the following precautions could lead to serious or possibly
fatal injury. Always heed these precautions.
• Always connect to 100
Ω
or less when installing the Units. Not connecting
to a ground of 100
Ω
or less may result in electric shock.
• Always turn OFF the power supplies to the PLC, slaves, and communica-
tions before attempting any of the following. Not turning OFF the power
supplies may result in malfunction or electric shock.
• Mounting or dismounting Power Supply Units, I/O Units, CPU Units,
memory casettes, Master Units, or any other Units
• Mounting or dismounting circuits for Remote I/O Terminals with 3-tier
terminal blocks
• Assembling the Units or Racks
• Setting DIP switches or rotary switches
• Connecting or wiring the cables
• Connecting or disconnecting the connectors
!Caution
Failure to abide by the following precautions could lead to faulty operation or
the PLC or the system or could damage the PLC or PLC Units. Always heed
these precautions.
• Failsafe 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.
• Provide external interlock circuits, limit circuits, and other safety circuits in
addition to any provided within the PLC to ensure safety.
• Configure the control circuits to turn ON the power supply to I/O slaves
before turning ON the power supply to the PLC (Master Unit). If the I/O
slave power supply is turned ON after the PLC, correct operation may
temporarily not be possible.
• Do not attempt to disassemble, repair, or modify any Units. Any attempt to
do so may result in malfunction, fire, or electric shock.
• Do not drop the Unit or subject it to excessive vibration or shock.
• Be sure that all the Backplane mounting screws, slave mounting screws,
terminal screws, and cable connector screws are tightened to the torque
specified in the relevant manuals. Incorrect tightening torque may result in
malfunction.
• Wire correctly according to specified procedures.