Omron CJ2 User Manual page 23

Do not attempt to take any Unit apart while the power is being supplied.
Doing so may result in electric shock.
Do not touch any of the terminals or terminal blocks while the power is being
supplied. Doing so may result in electric shock.
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.
• The PLC will turn OFF all outputs when its self-diagnosis function detects
any error or when a severe failure alarm (FALS) instruction is executed. As
a countermeasure for such errors, external safety measures must be pro-
vided 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 countermea-
sure 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 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.
Confirm safety before transferring data files stored in the file memory (Mem-
ory Card or EM file memory) to the I/O area (CIO) of the CPU Unit using a
peripheral tool. Otherwise, the devices connected to the output unit may mal-
function regardless of the operation mode of the CPU Unit.
Fail-safe measures must be taken by the customer to ensure safety in the
event of incorrect, missing, or abnormal signals caused by broken signal
lines, momentary power interruptions, or other causes. Serious accidents
may result from abnormal operation if proper measures are not provided.
CJ2 CPU Unit Hardware User's Manual
WARNING
17