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ERROR Mode :-
The ERROR mode is a shut-down mode as a result of self-diagnosis. The PLC enters the ERROR mode if internal
trouble is detected by self-diagnosis. In this mode, program execution is stopped and all outputs are switched off.
The cause of the Error-down can be confirmed by connecting to OIL-DS software. To exit from the ERROR mode,
execute the Error Reset command from the OIL-DS, or cycle power OFF and then ON again.
Self-Diagnosis :-
Checks the proper operation of the PLC itself. If an error has detected and cannot be recovered by re-tries, the V200
moves into ERROR mode.
Self-Diagnosis is performed in firmware at two stages:
A
) At initialization (Power ON)
e.g. RAM, ROM check, IO mismatch check.
B) In continuous while loop
e.g. IO bcc check, scan time check.
If an error is detected by the self-diagnostic check of the PLC, the error messages and related information shown on
the following pages will be recorded in the PLC event history table. If the error is severe and continuation of operation
is not possible, the PLC turns OFF all outputs and stops the operation (ERROR mode).
The latest 30 error messages are stored in the event history table. This event history table can be displayed on the
OIL-DS. (Power ON/OFF is also registered) If the PLC has entered into ERROR mode, connect the OIL-DS to the
PLC to confirm the error message in the event history table. This information is important to recover from an error.
In the event history table, No.1 message indicates the latest event recorded. Each column shows the following
information:
Date: The date when the error has detected
Time: The time when the error has detected
Event: Error message
Count: Number of times the error has detected by retry action
Info
n: Related information to the error detected
Mode: PLC operation mode in which the error has detected (INIT. means the power-up initialization)
Down: Shows the PLC has entered into ERROR mode by the error detected
If the PLC is in the ERROR mode, operations to correct the program are not accepted.
In this case, execute the Error reset operation by the OIL-DS to return the HALT mode before starting the correc-
tion operation.
Configuration registers (MW01 and MW02):
(1) These configuration devices are set by the PLC operating
system.
These devices are read only for user.
(2) Devices marked as (down) are set in the ERROR mode. These type of errors will cause the PLC to enter in the
Error mode.
(3) Devices marked as (alarm) are set when the corresponding condition has occurred. PLC continues to be in the
same mode if these errors occurs.