Application Precautions - Omron GRT1 - 11-2007 Operation Manual

Application Precautions

!Caution The operating environment of the PLC System can have a large effect on the
5 Application Precautions
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• Locations subject to dust (especially iron dust) or salts.
• Locations subject to water, oil, or chemicals (Digital I/O Units)
• Locations subject to acid or chemicals.
• Locations subject to shock or vibration.
Take appropriate and sufficient countermeasures when installing systems in
the following locations:
• Locations subject to static electricity or other forms of noise.
• Locations subject to strong electromagnetic fields.
• Locations subject to possible exposure to radioactivity.
• Locations close to power supplies.
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.
Observe the following precautions when using the Slice I/O Units.
• 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.
• Provide external interlock circuits, limit circuits, and other safety circuits in
addition to any provided within the PLC to ensure safety.
• Use the power supplies specified in the operation manuals.
• If the system is installed at a site with poor power supply conditions, take
appropriate measures to ensure that the power supply remains within the
rated voltage and frequency specifications.
• Provide circuit breakers and other safety measures to provide protection
against shorts in external wiring.
• Always ground the system to 100 Ω or less when installing the system to
protect against electrical shock.
• Mount the PLC securely on DIN Track or with screws.
• Always turn OFF the power supply when mounting a Slice I/O Unit.
• Always turn OFF the communications power supply and the power sup-
plies to the PLC and Slaves before attempting any of the following.
• Mounting or removing a Unit such as an I/O Unit, CPU Unit, Memory
Cassette, or Master Unit.
• Mounting or removing Remote I/O Terminal circuit sections.
• Assembling any devices or racks.
• Setting rotary switches.
• Connecting or wiring cables.
• Connecting or disconnecting connectors.
• Do not attempt to disassemble, repair, or modify any Units.
• Be sure that all the terminal screws are tightened to the torque specified
in the relevant manuals. Loose screws may cause fire, malfunction, or
damage the Unit.
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