Omron CJ1W-SCU22, Руководство по эксплуатации, Страница: 302 / 478

9 Troubleshooting and Maintenance
9-24
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
Note The system settings can not be changed unless the power supply is cycled, the Unit is restarted,
or the port is restarted. Refer to 1-8 Basic Operating Procedure for details.
Error conditions Confirmation of
device variable
for CJ-series Unit,
etc.
Cause Remedy
Serial
communications
mode
Indicator
status
Status
information,
etc.
Serial communi-
cations mode is
set to Modbus-
RTU Slave Mode. The RD @ /SD @
indicators flash,
and an error
response was
returned to the
host.
There is no
transmission
error. *_P1(orP2)_TransErr
Sta (Transmission
Error Status) is set to
0000 hex. A command was sent
from the host with
incorrect parameters. Review the host's settings
and program (such as param-
eter settings) based on the
response contents.
There is a
transmission
error. *_P1(orP2)_TransErr
(Transmission error) is
set to TRUE, or any of
*_P1(orP2)_OverRun
Err (Overrun Error),
*_P1(orP2)_FramingE
rr (Framing Error),
*_P1(orP2)_ParityErr
(Parity Error),
*_P1(orP2)_FCSErr
(FCS Check Error) is
set to TRUE. The communications
conditions and baud
rate do not match the
settings at the host. Review the System Settings,
the host's settings and pro-
gram (such as commands
and frame format) based on
the response contents, and
the transmission error codes
in *_P1(orP2)_TransErrSta
(Transmission Error Status).
The RD @ /SD @
indicators flash,
but sometimes
there is no
response
returned.
There is a
transmission
error some-
times. *_P1(orP2)_TransErr
(Transmission error) is
set to TRUE, or any of
*_P1(orP2)_OverRun
Err (Overrun Error),
*_P1(orP2)_FramingE
rr (Framing Error),
*_P1(orP2)_ParityErr
(Parity Error),
*_P1(orP2)_FCSErr
(FCS Check Error) is
set to TRUE. The baud rate is out-
side the allowable
range, and the stop
bits do not match,
which causes the bits
to be out of alignment. Review the System Settings.
Review the host's settings
and program (such as baud
rate and frame format).
There is a
transmission
error some-
times. Terminating resis-
tance switch (TERM
ON/OFF) status Cables are incorrectly
connected.
The RS-422A/485
port terminating resis-
tance setting is incor-
rect.
Adapters such as the
NT-AL001 are incor-
rectly wired or the ter-
minating resistance is
incorrectly set.
Check the wiring.
Turn ON the terminating
resistance at two last loca-
tions (host side or Unit side).
Turn OFF the terminating
resistance of other Units.
There is a
transmission
error some-
times. *_P1(orP2)_TransErr
Sta (Transmission
Error Statsu) is not set
to 0000 hex. Transmission errors
occur that are caused
by noise interference. Use shielded twisted-pair
cables.
Lay power lines separately by
using ducts.
Review the installation envi-
ronment to reduce noise inter-
ference.
Programming retry process-
ing for communications if nec-
essary.