Operating Environment Precautions - Omron GRT1 - 27-11-2006 Operation Manual

Operating Environment Precautions

!WARNING
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Operating Environment Precautions

!Caution Do not operate the Unit in the following places:
• The PLC outputs may remain ON or OFF due to deposits on or burning of
the output relays, or destruction of the output transistors. As a counter-
measure for such problems, external safety measures must be provided
to ensure safety in the system.
• When the 24V DC output (service power supply to the PLC) is overloaded
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.
• SmartSlice I/O Terminals will continue operating even if one or more I/O
Units is removed from or falls out of the SmartSlice I/O Terminal, i.e., the
other I/O Units will continue control operations, including outputs. As a
countermeasure for such a possibility, external safety measures must be
provided to ensure safety in the system.
The CPU Unit refreshes I/O even when the program is stopped (i.e., even in
PROGRAM mode). Confirm safety thoroughly in advance before changing the
status of any part of memory allocated to Output Units, Special I/O Units, or
CPU Bus Units. Any changes to the data allocated to any Unit may result in
unexpected operation of the loads connected to the Unit. Any of the following
operations may result in changes to memory status.
• Transferring I/O memory data to the CPU Unit from a Programming
Device
• Changing present values in memory from a Programming Device
• Force-setting/-resetting bits from a Programming Device
• Transferring I/O memory files from a Memory Card or EM file memory to
the CPU Unit
• Transferring I/O memory from a host computer or from another PLC on a
network
• Locations subject to direct sunlight.
• Locations subject to temperatures or humidities outside the range speci-
fied 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 salt.
• Locations subject to exposure to water, oil, or chemicals.
• Locations subject to shock or vibration.
Provide proper shielding when installing in the following locations:
• Locations subject to static electricity or other sources of noise.
• Locations subject to strong electromagnetic fields.
• Locations subject to possible exposure to radiation.
• Locations near to power supply lines.
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