IDEC MICROSmart FC6A Series, User Manual

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FC6A S
ERIES
MICROS
MART
U
SER
’
S
M
ANUAL
FC9Y-B1722 13-21
13: T
ROUBLESHOOTING
Troubleshooting Diagram 14
*1 See Chapter 6 "Modbus RTU Master Communication" - "Communication Completion and Communication Error" in the "FC6A Series MICROSmart
Communication Manual".
Confirm slave settings again.
Make sure that the slave is compatible
with the function code.
Make sure that the slave number and
communication settings are correct.
Are communication
parameters equal at master and
slave?
Modbus RTU master
communication does not work.
YES
NO
YES
NO
YES
Confirm communication settings using
WindLDR.
Confirm the slave number (high-order
byte) and error code (low-order byte)
*1
.
Make sure that slave address settings are
correct.
Turn on the request execution device.
YES
Is it clear which
request has an error?
NO
See the request table to find which request
has an error and what error occurred.
YES
01h (function error)?
NO
02h (access destination error)?
NO
YES
03h (device
quantity error, 1-bit write
data error)?
NO
YES
16h (timeout error)?
NO
NO
Make sure of the valid slave address
range and master settings.
YES
Data size and actual data may not
match. Make sure that slave settings
and hardware are correct (without noise
and failure).
When the communication
error status is configured, is the error
information stored?
*1
Set to use a request
execution device and the device
is not turned on.