Mitsubishi A1SJ61BT11 User Manual page 239

13 TROUBLESHOOTING
Trouble description
Unable to communicate from the
master station (remote register RWw)
to the local station (remote register
RWr).
Unable to communicate from the local
station (remote register RWw) to the
master station (remote register RWr).
Unable to stop data link.
Unable to restart data link.
Parameter cannot be registered in
2
E PROM.
Remote/local station does not start up.
Faulty stations cannot be detected.
Faulty stations arise due to
transmission speed.
The abnormal completion bit turns on
when executing a dedicated
Xn1 (host station data link status) does
not turn ON.
Link special relay (SB)/link special
resister (SW) are not updated
correctly.
Details to be checked
Is the corresponding local station performing
data link?
Does the occupied station count setting of
the local station match the station
information of the master station?
Is data written to the correct address of
remote register RWw (buffer memory) at the
master station?
Is data read from the correct address of the
remote register RWr (buffer memory) at the
local station?
Is the station incorrectly set as reserved?
Did the station number overlap?
Is the corresponding local station performing
data link?
Is data written to the correct address of
remote register RWw (buffer memory) at the
local station?
Is data read from the correct address of the
remote register RWr (buffer memory) at the
master station?
Is the station incorrectly set as reserved?
Did the station number overlap?
Is the data link stop (SB0002) turned on?
Did an error occur?
Is the data link stop (SB0000) turned on?
Did an error occur?
Is the parameter registration request (YnA)
2
to the E PROM on?
Any errors occurred?
Are the station information in the parameters
and the settings as the module which does
not start up consistent?
Overlapping with other module's station
number?
Set as an error-invalid station?
Did the station number overlap?
Is it possible to specify faulty station from the
communication status with other stations
(SW0080 to 83)?
Can communicate normally when changed
to slower transmission speed like 156 kbps?
Did an error occur?
Is an automatic refresh parameter set?
Is the program not created so that it
executes the FROM/TO instruction multiple
times during one sequence scan?
Is the sequence scanning speed not far
higher than the link scanning speed when
the FROM/TO instruction is present?
13 - 3
Confirmation action
Check the LED indication of the corresponding local
station.
Check the communication status of the master
station with other stations (SW0080 to SW0083).
Verify the sequence program.
Verify the sequence program.
Verify the parameters.
Verify the station number.
Check the LED indication of the corresponding local
station.
Check the communication status of the master
station with other stations (SW0080 to SW0083).
Verify the sequence program.
Verify the sequence program.
Verify the parameters.
Verify the station number.
Verify the sequence program.
Verify the data link stop result (SW0045).
Verify the sequence program.
Verify the data link restart result (SW0041).
Verify the sequence program.
2
Verify the E PROM registration status (SW00B9).
Verify the parameters.
Verify the station number setting switch.
Verify the parameters.
Verify the station number.
Verify the faulty station switch setting.
Verify if the wiring is correct.
Verify if the cable shield has been grounded.
Verify the CPU's error code.
Verify the master station's error code.
Set the automatic refresh parameter using an RRPA
instruction.
Reduce the number of FROM/TO instructions in the
program.
Add the data link priority signal (XnC), as b contact,
to the start contact of the FROM/TO command.
MELSEC-A