Problems Due To Incorrect Parameter Settings; Troubleshooting Using Led Indications; Errors Caused By The Master Unit - Mitsubishi Electric A1SJ71DN91 User Manual

8. TROUBLESHOOTING
8.1.2

Problems due to incorrect parameter settings

Symptom
Parameters Cannot be Set by
Sequence Program
(Parameter set complete (Xn7)
does not turn ON after parameter
set request (Y(n+1)7) turns ON.)
Parameter settings made by the
sequence program are ignored.
Parameter settings made by the
configuration software are
ignored.

8.2 Troubleshooting Using LED Indications

8.2.1

Errors caused by the master unit

RUN L.RUN MS
LED LED LED LED
Green Green
l l
l

O O

¥
O
Refer to the following tables to determine the appropriate remedy for problems arising due to
incorrect parameters or an incorrect sequence program.
Is refresh request (Y(n+1)1) ON before parameter set
request (Y(n+1)7) turns ON? Also, is refresh request
(Y(n+1)1) ON before parameter set complete (Xn7)
turns ON?
Is FFFF stored in the host station number storage
H
area of buffer memory?
Have parameter settings made by the sequence
program been disabled?
Have the parameter settings made by the
configuration software been disabled using the
configuration software settings?
Determine the cause of the error from the LED indicator status and take the appropriate
remedy.
NS
Status
Normal operation
l
PC power supply is not turned
ON.

Abnormal DN91 unit
Error is caused by another unit.
Abnormal DN91 unit

Parameters being loaded
Check Item
Check Item
None
Is PC power supply turned ON? Turn ON the power supply.
Correctly mounted in base unit? Correctly mount in base unit.
Is DN91 unit defective?
Is another unit (including the
base unit) defective?
Is DN91 unit defective?
Wait and see
l : Lit O : not lit ¥: Flashing ¥ r: Flashing (random)  : Undetermined
−
8 5
MELSEC-A
Remedy
Ensure refresh request (Y(n+1)1) does
not turn ON between parameter set
request (Y(n+1)7) turning ON and
parameter set complete (Xn7) turning
ON.
Store a station number from 0 to 63 in
the host station number storage area of
buffer memory.
Set FFFF as the host station number in
H
buffer memory with the sequence
program.
Change the parameter settings, referring
to 6.3 Setting Parameters with the
Configuration Software.
Remedy
None
Repair or replace the DN91 unit.
Repair or replace the unit.
Repair or replace the DN91 unit.
DN91 unit is defective if flashing
continues. Repair or replace the
DN91 unit.