Safety Precautions - Omron SYSMAC CS Series Operation Manual

Safety Precautions

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Safety Precautions

!WARNING
!WARNING
!WARNING
!WARNING
Do not attempt to take any Unit or Board apart while power is being supplied.
Doing so may result in electric shock.
Do not touch live terminals. Electric shock will result.
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 similar safety
measures must be provided in external control circuits.
• When using a CS1D-CPU@@P Process-control CPU Unit, the CS1D
Duplex System will stop operating and all outputs will be turned OFF in
the following cases:
• The self-diagnostic function detected errors at the same time in both
the active side (CPU Unit or Loop Controller) and the standby side
(CPU Unit or Loop Controller).
• A SEVERE FAILURE ALARM (FALS) instruction is executed and gen-
erated fatal errors at the same time in both the active CPU Unit and the
standby CPU Unit.
• The self-diagnostic function detected an error while operating in sim-
plex mode or performing duplex initialization in duplex mode.
• A SEVERE FAILURE ALARM (FALS) instruction was executed and
generated a fatal error while operating in simplex mode or performing
duplex initialization in duplex mode.
Unexpected operation, however, may still occur for errors in the I/O con-
trol section, errors in I/O memory, and other errors that cannot be
detected by the self-diagnosis function. As a countermeasure for all such
errors, external safety measures must be provided to ensure safety in the
system.
• When a CS1W-LCB01 or CS1W-LCB05 Loop Control Board is mounted
in a CS1-H CPU Unit, the CPU Unit will stop operating and all outputs will
be turned OFF if the self-diagnostic function detected an error or a
SEVERE FAILURE ALARM (FALS) instruction was executed. As a coun-
termeasure 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 deposition 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 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.
Check the following items before starting to run the Loop Controller:
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