Operating Environment Precautions - Omron CJ1W-NC271 - 12-2009 Operation Manual

Operating Environment Precautions

!Caution Execute online editing only after confirming that no adverse effects will be
!Caution Confirm safety at the destination node before transferring a program to
4 Operating Environment Precautions
!Caution Do not operate the control system in the following locations:
!Caution Take appropriate and sufficient countermeasures when installing systems in
• Emergency stop circuits, interlock circuits, limit circuits, and similar safety
measures must be provided in external control circuits.
• The PLC will turn OFF all outputs when its self-diagnosis function detects
any error or when a severe failure alarm (FALS) instruction is executed.
As a countermeasure for such errors, external safety measures must be
provided to ensure safety in the system.
• The PLC or PCU outputs may remain ON or OFF due to deposits on or
burning of the output relays, or destruction of the output transistors. As a
countermeasure for such problems, external safety measures must be
provided to ensure safety in the system.
• When the 24-V DC output (service power supply to the PLC) is over-
loaded or short-circuited, the voltage may drop and result in the outputs
being turned OFF. As a countermeasure for such problems, external
safety measures must be provided to ensure safety in the system.
• External safety measures must also be taken to ensure safety in the event
of unexpected operation when connecting or disconnecting the PCU's
connectors.
caused by extending the cycle time. Otherwise, the input signals may not be
readable.
another node or changing contents of the I/O memory area. Doing either of
these without confirming safety may result in injury.
• Locations subject to direct sunlight.
• Locations subject to temperatures or humidity outside the range specified
in the specifications.
• Locations subject to condensation as the result of severe changes in tem-
perature.
• Locations subject to corrosive or flammable gases.
• Locations subject to dust (especially iron dust) or salts.
• Locations subject to exposure to water, oil, or chemicals.
• Locations subject to shock or vibration.
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.
4
xxv