Omron CJ Series, Operation Manual

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1 Intended Audience
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1 Intended Audience
This manual is intended for the following personnel, who must also have
knowledge of electrical systems (an electrical engineer or the equivalent).
•
Personnel in charge of installing FA systems
•
Personnel in charge of designing FA systems
•
Personnel in charge of managing FA systems and facilities
2 Safety Precautions
!WARNING Provide safety measures in external circuits (i.e., not in the
Programmable Controller), including the following items, to ensure
safety in the system if an abnormality occurs due to malfunction of
the PLC or another external factor affecting the PLC operation. Not
doing so may result in serious accidents.
•
Emergency stop circuits, interlock circuits, limit circuits, and other
safety measures must be provided in external control circuits.
•
The PLC will turn OFF all outputs when its self-diagnosis function
detects an error or when a SEVERE FAILURE ALARM instruction
(FALS(007)) is executed. As a countermeasure for such errors,
external safety measures must be provided to ensure safety in the
system.
•
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 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) 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.
!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 unexpected operation of the loads
connected to the Unit. Any of the following operation 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 When performing any of the following operations, always check the network
address and node address of the other node (PLC) and the node address
and unit number of the mounted Unit (PLC CPU Bus Unit or Special I/O Unit)