Omron CJ1W-DRM21, CS1W-DRM21 operation manual Operating Environment Precautions

Operating Environment Precautions 4

measure for such problems, external safety measures must be provided to ensure safety in the system.

•When the 24-VDC output (service power supply to the PC) 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.

The CPU Unit refreshes I/O even when the program is stopped (i.e., even in !WARNINGPROGRAM 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 PC on a network.

Execute online edit only after confirming that no adverse effects will be caused by extending the cycle time. Otherwise, the input signals may not be

!Cautionreadable.

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 Unit in any of the following locations.

•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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