6F3B0253

Basic Hardware and Function 285

10. Troubleshooting
10.1.4 Input check

If the program is running but the external input signal is not read normally, check the

following points:

Is the input status LED If not, check the input v oltage at the
changed ON/OFF according T1-16S’s input terminals.
to the corresponding input If the v oltage is not normal, c heck the input
device operation ? dev ice and the cable.
If the volt age is normal, the T1-16S’s i nput
Yes circuit may be faulty.
Connect the programming If the monit ored X device state is identic al
tool, and monitor the to t he state of the input status LED, the
corresponding X device state cause may lie in t he user program or in the
in RUN mode env ironment.
Not normal
Check whether the X device If it is forced, release the force designation
is forced or not then execute the EEPR OM write
operation.
Not forced
Check whether the I/O If identical, the T1-16S’s internal circuit or
allocation table is ident ical to the input circui t may be faulty.
the actual I/O conf iguration
Not identical
Execute the automatic I/O If it becomes identical, execute the
allocation, and check whether EEPROM write operation.
the I/O allocation table is now
identical to the actu al I/O
configuration
Still not identical
Is the allocation mis match for If so, the card, module or expansion unit
a specific I/O module? may be faulty. F or expansion unit, check
the expansion cable also.