
B–64115EN/01
8. TROUBLESHOOTING
457
If the I/O Link is not established, if the signals from an I/O device cannot
be input normally to the CNC, or if the signals from the CNC cannot be
output to an I/O device, the probable causes include the following:
D The I/O device is not turned on, or the power supply is not at the
appropriate voltage.
D The I/O Link cable is not connected correctly or appropriately.
D The input/output signals are not connected correctly.
D I/O Link allocation is not performed, or is not performed properly.
If “NO I/O DEVICE” is displayed on the alarm screen of the PMC, no I/O
devices are recognized.
By selecting [PMCDGN], [IOCHK], and [IOLNK] in this order from the
PMC screen, the I/O devices recognized by the CNC are displayed. From
this screen, the devices that are connected normally can be determined.
Screen display example
GROUP ID KIND OF UNIT00
00 A9 I/O MODULE01
01 A8 OTHER UNIT
This example indicates that the I/O Link is as shown in the figure below.
Operator’s panel
I/O module
JD1A
I/O module for
connector panel
JD1B
JD1A
JD1B
JD1A
Control unit
Group 0
Group 1
8.8
INPUT FROM AND
OUTPUT TO I/O
DEVICES CANNOT
BE PERFORMED
INPUT/OUTPUT
CANNOT BE
PERFORMED
PROPERLY
Causes and actions
D PMC alarm NO I/O
DEVICE
D IOCHK screen of the
PMC