Omron CJ2 CPU UNIT SOFTWARE User Manual page 33

• Changing the present value of any word or any set value in memory.
• Do not attempt to disassemble, repair, or modify any Units. Any attempt to do so may result in mal-
function, fire, or electric shock.
• Do not drop the PLC or subject abnormal vibration or shock to it.
• The life of the battery will be reduced if the PLC is left for a period of time without a battery
installed and without power supply, and then a battery is installed without turning ON the power
supply.
• Replace the battery as soon as a battery error occurs or as soon as the specified battery backup
time expires. Be sure to install a replacement battery within two years of the production date
shown on the battery's label.
• Before replacing the battery, turn ON power for at least 5 minutes before starting the replacement
procedure and complete replacing the battery within 5 minutes of turning OFF the power supply.
Memory contents may be corrupted if this precaution is not obeyed.
• If the Battery Error Flag is used in programming the application, confirm system safety even if the
system detects a battery error before you replace the battery while the power is ON.
• Do not short the battery terminals or charge, disassemble, heat, or incinerate the battery. Do not
subject the battery to strong shocks. Doing any of these may result in leakage, rupture, heat gen-
eration, or ignition of the battery. Dispose of any battery that has been dropped on the floor or oth-
erwise subjected to excessive shock. Batteries that have been subjected to shock may leak if they
are used.
• UL standards require that only an experienced engineer can replace the battery. Make sure that
an experienced engineer is in charge of battery replacement. Follow the procedure for battery
replacement given in this manual.
• Dispose of the product and batteries according to local ordinances as they apply.
• If the I/O Hold Bit is turned ON, the outputs from the PLC will not be turned OFF and will maintain
their previous status when the PLC is switched from RUN or MONITOR mode to PROGRAM
mode. Make sure that the external loads will not produce dangerous conditions when this occurs.
(When operation stops for a fatal error, including those produced with the FALS(007) instruction,
all outputs from Output Unit will be turned OFF and only the internal output status will be main-
tained.)
• Unexpected operation may result if inappropriate data link tables or parameters are set. Even if
appropriate data link tables and parameters have been set, confirm that the controlled system will
not be adversely affected before starting or stopping data links.
• Write programs so that any data that is received for data link communications is used only if there
are no errors in the CPU Units that are the sources of the data. Use the CPU Unit error informa-
tion in the status flags to check for errors in the source CPU Units. If there are errors in source
CPU Units, they may send incorrect data.
• All CPU Bus Units will be restarted when routing tables are transferred from a Programming
Device to the CPU Unit. Restarting these Units is required to read and enable the new routing
tables. Confirm that the system will not be adversely affected before transferring the routing
tables.
• Tag data links will stop between related nodes while tag data link parameters are being trans-
ferred during PLC operation. Confirm that the system will not be adversely affected before trans-
ferring the tag data link parameters.
• If there is interference with network communications, output status will depend on the devices that
are being used. When using devices with outputs, confirm the operation that will occur when there
is interference with communications, and implement safety measures as required.
CJ2 CPU Unit Software User's Manual 27