Omron C200HW-CORT21-V1, Operation Manual

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Troubleshooting
Section 7-2
101
I/O data communication problems (continued)
Description Possible cause Possible remedy
Another Special I/O Unit makes use of the
same data area(s), e.g. C200HW-PRM21, -
DRM21, -PRT21, -DRT21.
When areas overlap, one Unit overwrites the
data area of the other, depending on their
respective Machine Numbers.
Check the mapping of the C200HW-CORT21-
V1 and the other Special I/O Unit. If an
overlap exists, the Unit settings of one of the
units should be changed. Adapt the PLC
program accordingly.
The Unit is defective. Replace the C200HW-CORT21-V1.
Data in the mapped
PLC area is being
reset. Data that is mapped in the IR- or LR area is
reset when
•
The Host PLC is switched between
RUN / MONITOR mode and PROGRAM
mode.
•
A fatal PLC error occurs (see section 6-4)
If the Host PLC was not switched to / from
PROGRAM mode, check if a fatal PLC error
has occurred and try to solve the cause of the
error. Refer to the Operation Manual of the
PLC for details.
The Unit is defective. Replace the C200HW-CORT21-V1.
Other nodes update their SDO data more
frequently than the I/O refresh rate of the host
PLC. If the same SDO is received twice or
more per PLC cycle, only the last data will be
transferred to the PLC. Reduce the host PLC's cycle time (faster CPU
type, move control tasks and I/O to another
PLC), or
Reduce the update rate of the transmitting
node to match the PLC cycle time.
Not all CANopen
PDOs sent by other
nodes arrive in the
host PLC.
Other nodes transmit more SDOs linked to the
unit, than can be processed by the unit's CAN
interface. The CAN interface transmits an
Emergency message (receive queue overflow). Reduce the number of output data objects and
RPDOs.
Reduce the update rate of the transmitting
nodes.
The Unit transmits all data messages, but the
processing at the receiving node takes longer
than the Unit's I/O refresh cycle Increase the PLC scan time, or only perform
I/O refreshes with the Unit when necessary
(by IOWR command). Not all CANopen
PDOs sent by the
Unit arrive at other
nodes.
The host PLC produces more (changes of state
in) data objects than can be transmitted by the
CAN interface. The CAN interface transmits an
Emergency message (transmit queue
overflow). Reduce the number of input data objects on
TPDOs.
Increase the PLC scan time
ERR LED is
switched ON. An application error was detected. IR n+3.14 is
set. Restart the Unit. If this does not help, replace
the Unit.
Message communication problems
Description Possible cause Possible remedy
IOWR instruction
not executed
successfully. The IOWR instruction contains syntax errors.
(EQ-flag is not set) Check if the correct Machine number and
message length is specified in the IOWR
instruction.
The control code is invalid or the specified
message length does not correspond with the
function indicated by the control code.
(EQ-flag is not set).
The contents of the message is invalid.
Read the error log to find the cause.
Check if the control code lies within the range
#0001 to #0004.
Check the message length.
Check the contents of the message.
The Unit is defective. Replace the C200HW-CORT21-V1.