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Chapter 9 Diagnosis function
9-6
9.2 Diagnosis during power on
Cnet I/F module performs self-diagnosis test and checking of PLC CPU & interface as in the sequence below.
[Table 9.4] Checking sequence when powered on
CHECKING
SEQUENCE
CHECKING ITEM
LED LIGHTING SEQUENCE
1
LED display check
All LEDs ON/OFF as executed
2
Self-memory check
LED '0' On
3
Flash memory check
LED '1' On
4
UART check
LED '2' On
5
Common memory check
LED '3' On
6
PLC interface check
LED '4' On
7
Operation mode check
LED '5' On
1)
Upon being powered on, all module’s LEDs are turned ON for approx. 1 sec. and then OFF to check LED display.
The LED if not turned on during the first lighting ON is in error.
2)
After LED check, LEDs from No.1 to No.5 are turned ON by turns to execute self-diagnosis and checking of PLC
CPU & interface.
3)
LED display during self-diagnosis and PLC Interface test is turned ON according to the sequence below.
0
Æ
1
Æ
2
Æ
3
Æ
4
Æ
5
4)
After self-diagnosis is over in the sequence above, it is switched to the LED display status of normal operation
mode according to operation mode and basic setting to start normal operation.
5)
If not agreed with the displaying specification of self-diagnosis, check connection & installation status of base slot
and then supply power again.
6)
If still operated as not agreed with the LED display items above even for normal installation of module, the applied
module hardware seems in error. Please contact service station.
Remark
[Note1] When [Operation mode check] in sequence7 of self-diagnosis checking sequence is applied as powered on,
LED No.5 is turned On-Off in a twinkling, which may be hard to recognize by naked eye, however, this is not
indicating that Cnet I/F module is in error if switched to normal operation mode later.