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Checking Operations for CS-series, C200HX/C200HG/C200HE-(Z)E, and C200HS Master Units
Section 6-2
When an error occurs in a Slave, the Slave can be identified from the status of
the Master’s indicators or from the status flags in the PLC’s Special I/O Unit
Area.
Error
Probable cause
Possible remedy
The Master Unit’s
RUN indicator is
OFF
The PLC’s power is OFF.
Turn the PLC’s power supply ON.
The same unit number has been set
on another Special I/O Unit, causing
an I/O UNIT OVER error in the PLC.
Check that the same unit number is not used by more than
one Special I/O Unit and restart the PLC. In particular, when
the usable node number setting is IN0 to IN15 and OUT0 to
OUT15, check that the next unit number after the one set on
the Master Unit is not set on another Special I/O Unit.
The unit number has been set outside
the specified range, causing an I/O
UNIT OVER error in the PLC.
Check that the unit number is set within the range specified
for Special I/O Units and restart the PLC.
CS-series:
Unit numbers 0 to F can be set when the maximum number
of Slaves setting is 16 (pin 1 OFF); Mountable number of
Master Units is 16 when using 10 words as a Special I/O
Unit; Usable node number setting is IN0 to IN7 and OUT0 to
OUT7
Unit numbers 0 to E can be set when the maximum number
of Slaves setting is 32 (pin 1 ON); Mountable number of Mas-
ter Units is 8 when using 20 words as a Special I/O Unit;
Usable node number setting is IN0 to IN15 and OUT0 to
OUT15
C200HX-CPU3
@
-(Z)E/-CPU4
@
-(Z)E, C200HX-CPU3
@
-(Z)E/
-CPU4
@
-(Z)E, C200HE, and C200HS PLCs:
Unit numbers 0 to 9 can be set when the maximum number
of Slaves setting is 16 (pin 1 OFF); Mountable number of
Master Units is 10 when using 10 words as a Special I/O
Unit; Usable node number setting is IN0 to IN7 and OUT0 to
OUT7
Unit numbers 0 to 8 can be set when the maximum number
of Slaves setting is 32 (pin 1 ON); Mountable number of Mas-
ter Units is 5 when using 20 words as a Special I/O Unit;
Usable node number setting is IN0 to IN15 and OUT0 to
OUT15
C200HX-CPU5
@
-(Z)E/-CPU6
@
-(Z)E/-CPU8
@
-(Z)E and
C200HG-CPU5
@
-(Z)E/-CPU6
@
-(Z)E PLCs:
Unit numbers 0 to 9 or A to F can be set when the maximum
number of Slaves setting is 16 (pin 1 OFF); Mountable num-
ber of Master Units is 16 (when using 10 words as a Special
I/O Unit; Usable node number setting is IN0 to IN7 and OUT0
to OUT7
Unit numbers 0 to 8 or A to E can be set when the maximum
number of Slaves setting is 32 (pin 1 ON); Mountable number
of Master Units is 8 (when using 20 words as a Special I/O
Unit; Usable node number setting is IN0 to IN15 and OUT0 to
OUT15
The Master Unit’s
RUN indicator is
OFF
A Special I/O Unit error occurred in
the PLC because the usable node
number setting was changed with the
PLC power ON, but just the Master
Unit was restarted.
Turn the PLC OFF and then ON again.
A Special I/O Unit error occurred in
the PLC because the Master Unit is
not connected securely.
Turn the PLC OFF, make sure that the Master Unit is
mounted correctly, and then turn the PLC ON again. Replace
the Master Unit if the error recurs.
An input-output I/O table error
occurred in the PLC because the Mas-
ter Unit’s unit number or usable node
number setting was changed after the
I/O table was registered.
Register the I/O table again.
The Master Unit is faulty.
Replace the Master Unit.