Unit; Errors Originating In The Cpu Unit; Special I/O Unit Restart Bits - Omron CJ Series Operation Manual

Error and Alarm Processing
5-1-4

Errors Originating in the CPU Unit

ERH Indicator Lit and RUN Indicator Lit
Error
CPU Unit Monitor A response was not
Error returned from the CPU Unit
within the fixed interval.
ERH Indicator Lit and RUN Indicator Not Lit
Error
Unit Number Dupli- The Temperature Control Unit's unit number is
cation Error duplicated on another Special I/O Unit or is not
within the allowed range (00 to 94).
(The Temperature Control Unit occupies 20
words in the Special I/O Unit Area, so it is also
possible that these allocated words overlap.)
Special I/O Unit An installed Special I/O Unit does not match
Setup Error the Special I/O Unit registered in the I/O table.
I/O Bus Error An error occurred in the transfer of data
between the CPU Unit and another Unit.
CPU Unit WDT Error An error occurred in the CPU Unit
5-1-5

Special I/O Unit Restart Bits

The ERH Indicator will light when the Temperature Control Unit cannot oper-
ate normally because I/O refreshing is not being performed properly with Spe-
cial I/O Units. An error in the CPU Unit or I/O bus can interfere with I/O
refreshing.
RUN
ERC
ERH
The ERH and RUN Indicators will both be lit when I/O refreshing is not being
performed properly. Refer to the CJ-series Programmable Controllers Opera-
tion Manual (W393) for details.
Cause Control status
Control operation
will continue.
RUN
ERC
ERH
If a WDT (watchdog timer) error occurred in the CPU Unit because the Tem-
perature Control Unit's unit number was set incorrectly or there was an error in
the I/O bus, the ERH Indicator will light since I/O refreshing will not be per-
formed properly with the Temperature Control Unit.
Cause
After changing the contents of DM settings or eliminating the cause of an
error, the Unit must be restarted by turning the PLC's power ON again or tog-
gling (OFF → ON → OFF) the corresponding Special I/O Unit Restart Bit.
Lit
Not lit
Processing
Check the I/O refreshing interval.
Lit
Not lit
Control status
Control operation Correct the unit number set-
will stop. tings. Turn the power ON
again or restart the Unit.
Check that the sliding latches
connect all of the Units
securely and the End Cover is
locked. Turn the power ON
again or restart the Unit.
Section 5-1
Processing
75