Help !

I have a CNC mill c1988 with a Fanuc OM A control on it. It hasn't been used for a while since it was last moved, when i powered it up for the first time i got:

System Alarm 0412-08

920 Watchdog Timer

Any ideas ?

When you swicth it on the initial screen says
0412-08 in large text and breifly 0A0s-09 in small text before displaying the alarm.

You can't get out of the alarm screen and no keys on the fanuc keyboard apear to have any effect.

the backup battery voltage apears ok so i don't think its lost its memory.

the motherboard part no. is A16B-1010-0210/110
it has 3 cards in it : I/O C3, 3/4 Axis, Graphic/MPG.

Any help would be apreciated.

Cheers

Neil

 

The dreaded watchdog! Yea I hate that alarm. I think the manual basically tells you the processor or kernal has locked up. I have found that it could be as simple as a card on the mother board not seated properly or even a cable loose somewhere. I also had this happen once and it ended up being a problem with an encoder on a motor. This is the absolute worst alarm i have dealt with because it is so vague. Anything that is providing crucial information to the cpu that is not functioning at initialization can cause this. Swap til you drop is the order of business after you are satisfied with wiring and connections? It could also be the master/mother board itself. Hopefully you have another 0a system to use for board/ component verification. you could try a system dump at bootup but i doubt it will help. I think its reset and delete held high while powering the machine [email protected]

 

watchdog also caused by some intrupt getting on/off in very first cycle.