Our SLC-5/03 CPU module has a problem and can't function properly, the FAULT lamp sometimes blinking and sometimes steady red, so
the CPU can't start. When we tried to online with CPU, we got the message as below :
Fault Code = 0002h
Unexpected hardware watchdog timeout or an ASIC reset occured.
Cannot go online or upload from processor (no program).
You must perform download.
The problem is : we don't have backup program to be downloaded to CPU module, so we have to upload
the existing program or we have to start to create
the program from beginning.
Is there a way to upload existing program to solve the problem ?
Any help will be highly appreciated
Thanks in advance
OK, I have good news and bad news. Actually, only bad news. The fault message indicates your CPU has a fault or is completely expired. Either way, the program in the CPU memory is corrupt and cannot be uploaded to your PC. The only help I can give otherwise is to locate a printed-out copy of the PLC code and use that to develop a new program.
Once you have a new program, there is no guarantee that your processor is still good. Perhaps it is OK and you battery for the memory is bad. If you have had a power loss to the PLC, this is a likely scenario. You might want to invest in a new battery or a new EEPROM chip (non-volatile memory). The Allen-Bradley part number for the SLC-5/03 is 1747-M13. Once the program is downloaded to the CPU, it can be written to the EEPROM with the RS Logix software you are probably using. If you set bit s2/12 to 1, the CPU will then read the program from the EEPROM whenever it reboots.
> Our SLC-5/03 CPU module has a problem and can't function properly, the FAULT lamp sometimes blinking and sometimes steady red, <
Solid Red bad processor/power supply/mem module
Blinking Red initial factory condition no project loaded
> the CPU can't start. When we tried to online with CPU, we got the message as below :
> Fault Code = 0002h
> Unexpected hardware watchdog timeout or an ASIC reset occured.
> Cannot go online or upload from processor (no program).
> You must perform download.
> The problem is : we don't have backup program to be downloaded to CPU module, so we have to upload
> the existing program or we have to start to create
> the program from beginning. <
no program to upload - recreate from scratch
> Is there a way to upload existing program to solve the problem ?
> Any help will be highly appreciated <
A memory module with the application in it would have been a minimal investment on your part providing minimal downtime.
Unfortunately, Hindsight is 20/20.
Learn from your mistakes.
Back up applications before they are erased.
You may want to remove the IO cards from the rack.. the processor will fault
due to a hardware error.. but nothing in the processor will be running... it
might allow the comms to be active to allow you to upload
Use the serial port .. or try powering up in program mode ...
Cheers from: Jeremy Pollard, CET The Caring Canuckian!
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I am no expert but I had the same problem and it turn out to be the power supply on the rack. This surprised me since it worked fine as long as it was powered up.
>We just recently had this fault and replacing the power
>supply was the solution.
Hello nice to hear that.
Maybe you can help me to my problem. We got trouble on Slc5/03 many times. We encounter sudden stoppage of the machine. FLT fault flashes on CPU; these happen many times. Last time a month ago we encountered the same problem. Our IT reprogram it as usually did, and today again we encountered this trouble. It came to my mind that maybe there's a main problem that we didn't find out.
Anybody can help me? all of your comments will be highly appreciated.
As another poster mentioned it is not unusual for this kind of problem to be a power supply issue. I have also seen it be a rack issue. I would suggest replacing both along with the battery and see if that resolves your issue.
The manual suggests hardware fault:
- improper grounding,
- lack of surge suppression on outputs with inductive loads
- poor power source.
These are points that should have been dealt with at design/build/installation
Many years ago and after quite a few PSU changes, we found overloading the PSU external 24vDC supply for user devices, shutdown the power supply and erased PLC memory.