Watchdog Timer (Wdt) - Mitsubishi Electric MELSEC Q Series User Manual

(6) Clearing errors
A C Controller module can clear only continuation errors.
(a) Error clear procedure
To clear errors, complete the following procedure.
1.
Eliminate the reason for the error.
2.
Perform one of the following operations or
• Perform the error clear operations in [Diagnostics]  [CCPU diagnostics]  <<CCPU
diagnostics>>  "Clear error" in
• Execute the C Controller module dedicated function (CCPU_ClearError).
3.
The target error will be cleared.
(b) The status after clearing errors
When the C Controller module is restored with error clear, the special relay, special register and LED related to
the error return to the status before the error occurred.
When the same error occurs after error clear is performed, the error is registered to the event history again.
Errors occurring as a result of cause other than the C Controller module cannot be cleared.
[Example]
Since "SP. UNIT DOWN" is an error that occurred on the Q bus, the error cause cannot be resolved if error cancellation is
performed.
Refer to the following, and resolve the error cause.
 Page 394, CHAPTER 23 TROUBLESHOOTING
11.3

Watchdog Timer (WDT)

Watchdog timers are provided inside the C Controller module to detect failure of the hardware or user program.
The C Controller module has the following two different watchdog timers.
Item
The system watchdog timer monitors the system of the C
System watchdog timer Controller module, and is used to detect a fault in the hardware or
system software.
The user watchdog timer monitors the user programs, and is used
User watchdog timer
to detect an error in the hardware of user programs.
*1 : Cannot be set in Setting/monitoring tool for the C Controller module parameter.
Set the user watchdog timer by using a user program.
Note11.2
Q24DHCCPU-LS
Not supported by Q24DHCCPU-LS and Q26DHCCPU-LS.
158
Description
Q26DHCCPU-LS
processes.Note11.2
etting/monitoring tools for the C Controller module.
S
Q24DHC-V Q24DHC-VG
Note11.2
Q24DHC-LS Q26DHC-LS
: Supported : Supported with restrictions
CPU module
Q24DHC
Q26DHC
-LS
-V -VG -LS

 
Q12DC-V
Q12DC
-V
*1
