Omron DeviceNet 3G8F7-DRM21-E, Руководство по эксплуатации

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Operating Environment Precautions
4
3. The PLC outputs may remain ON or OFF due to deposition or burning of
the output relays or destruction of the output transistors. As a countermea-
sure for such problems, external safety measures must be provided to en-
sure safety in the system.
4. When the 24-VDC 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 mea-
sures must be provided to ensure safety in the system.
!WARNING
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 I/O Units, Special I/O Units, or CPU
Bus Units. Any changes to the data allocated to any Unit may result in unex-
pected operation of the loads connected to the Unit. Any of the following oper-
ation 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.
!Caution Confirm safety at the destination node before transferring a program to
another node or changing contents of the I/O memory area. Doing either of
these without confirming safety may result in injury.
4 Operating Environment Precautions
Do not install the PCI Board in any of the following locations.
• Locations subject to direct sunlight.
• Locations subject to temperatures or humidities outside the range
specified in the specifications.
• Locations subject to condensation as the result of severe changes in
temperature.
• 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.