8. Troubleshooting
Check that power is being supplied to the master and slave that customers use. If communication failure still
occurs, check the following.
Problem Possible Cause Solution
Communication
failure
The communication connector is
not securely connected.
Make sure that the communication
connector is securely connected.
Incorrect wiring of the communication
connector
Check the communication cable and
connector.
Refer to Section “2. Wiring” (pages 2, 3).
Burnout or imperfect contact on the
communication cable and the connector.
Check the communication cable and
connector.
Communication speed of the slave does
not match that of the master.
Set the same communication speed on the
master and the slave.
Refer to Section “3. Setting Communication
Parameters” (pages 4, 5).
The data bit, parity and stop bit of the
master do not correspond to those of
the slave.
Set the same data bit, parity and stop bit on
the master and the slave.
Refer to Section “3. Setting Communication
Parameters” (pages 4, 5).
The instrument number (address) of the
slave does not correspond to that of
the command.
Check the instrument number (address)
of the slave and the command.
Refer to Section “3. Setting Communication
Parameters” (pages 4, 5).
The instrument numbers (addresses) are
duplicated in multiple slaves.
Check that each slave has a different
instrument number (address).
Refer to Section “3. Setting Communication
Parameters” (pages 4, 5).
Make sure that the program is
appropriate for the transmission timing.
Check the program.
Refer to Sections “4.2 and 5.2
Communication Timing of the RS-485”
(pages 6, 21).
A non-existent command code has been
sent.
Check the command code.
The Write command data exceeds the
setting range of the slave.
Check the setting range of the slave.
Although
communication
is occurring, the
response is
negative
acknowledgement.
The controller cannot be written when
functions such as AT are performing.
Check the status of slave.
The KT4R is in front keypad operation
setting mode.
Return the controller to RUN mode.
For all other malfunctions, please contact our main office or dealers.
To Previous Page
Loading...
