Mitsubishi Electronics Q25HCPU User Manual

 

 

 

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MELSEC-Q

 

11   TROUBLESHOOTING 

 

11.4 Canceling of Errors 

The High Performance model QCPU can perform the cancel operation for errors only 

when the errors allow the CPU module to continue its operation. 

To cancel the errors, follow the steps shown below. 

1) Eliminate the cause of the error. 

2) Store the error code to be canceled in the special register SD50. 

3) Energize the special relay SM50 (OFF   ON). 

4) The error to be canceled is canceled. 

 

After the CPU module is reset by the canceling of the error, the special relays, special 

registers, and LEDs associated with the error are returned to the status under which 

the error occurred. 

If the same error occurs again after the cancellation of the error, it will be registered 

again in the error history. 

 

When multiple enunciators(F) detected are canceled, the first one with No. F only is 

canceled. 

 

POINT 

 

(1) When the error is canceled with the error code to be canceled stored in the 

SD50, the lower one digit of the code is neglected. 

(Example) 

If error codes 2100 and 2101 occur, and error code 2100 to cancel error code 

2101. 

If error codes 2100 and 2111 occur, error code 2111 is not canceled even if error 

code 2100 is canceled. 

 

(2) Errors developed due to trouble in other than the CPU module are not canceled 

even if the special relay (SM50) and special register (SD50) are used to cancel 

the error. 

(Example) 

The cause of "SP. UNIT DOWN" error cannot be removed even by using the 

special relay (SM50) and special register (SD50), because the error is 

developed on the Q bus. 

Refer to the error code list in Section 11.3.2 to remove the cause of the error.