Omron CJ - REFERENCE MANUAL 02-2010 Reference Manual page 33

CS/CJ/NSJ Series Instructions Reference Manual (W474)
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 hard-
ware manual for your PLC.
• 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 maintained.)
• 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 communica-
tions is used only if there are no errors in the CPU Units that are the
sources of the data. Use the CPU Unit error information 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 sys-
tem will not be adversely affected before transferring the routing tables.
• Tag data links between related nodes will stop while tag data link parame-
ters are being transferred during PLC operation. Confirm that the system
will not be adversely affected before transferring the tag data link parame-
ters.
• If there is interference with network communications, output status will
depend on the products that are being used. When using products with
outputs, confirm the operation that will occur when there is interference
with communications and implement safety measures.
• When creating an AUTOEXEC.IOM file from a Programming Device (a
Programming Console or the CX-Programmer) to automatically transfer
data at startup, set the first write address to D20000 and be sure that the
size of data written does not exceed the size of the DM Area. When the
data file is read from the Memory Card at startup, data will be written in
the CPU Unit starting at D20000 even if another address was set when
the AUTOEXEC.IOM file was created. Also, if the DM Area is exceeded
(which is possible when the CX-Programmer is used), the remaining data
will be written to the EM Area.
• A battery is mounted to a CJ-series CPU Unit when the Unit is shipped
from the factory. Also, the time is set on the internal clock. It is thus not
necessary to clear memory and set the clock before using a CJ-series
CPU Unit. This point differs from the CS-series CS1 CPU Units.
• The user program and parameter area data in the CJ2 CPU Units are
backed up in the built-in flash memory. The BKUP indicator will light on
the front of the CPU Unit when the backup operation is in progress. Do
PRECAUTIONS
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