Table of Contents
Advertisement
11. TROUBLESHOOTING
MELSEC-A
11.3 Troubleshooting
OFF
This section describes basic troubleshooting procedures for the AJ71C24.
The User's Manuals give information on PC CPU module troubleshooting.
11.3.1 Troubleshooting flow chart
The state of errors is described as follows:
f
Error
YES
See Section
11.3.2
when the
'RUN'
LEO is
AJ71C24
OFF?
turned OFF.
-
YES
See Section
11.3.3
when the neutral state does
not change.
YES
See
Section
11.3.4
when the
BC/N
(LEO
No.
16)
or
4-C/N
(LED
No. 20) is
turned
ON.
-
YES
If only 'NAK' is received,
an
'error code' is
Is only NAK received?
transmitted according to the
protocol.
Check
the error codes in Sections
11.1 or 11.2.
Is undecoded data
See Section
11.3.6
when undecoded data is
transmitted.
Advertisement
Table of Contents
