140 CPU 434 12 A 486 CONTROLLER

[YYK]

Due to Low Battery indication on the 140 CPU 434 12 A 486 CONTROLLER,  Battery of the PLC CPU was replaced with new one. But we see that there is a loss in stored memory program. All the connected devices to the PLC are not working.

How can I retrieve the program or upload the program in the PLC CPU to make it working ?

[MatthewM · Accepted solution]

The battery retains the program and data when the power supply to the CPU rack is turned off.  If the CPU is still powered up while you replace the battery, everything should remain as it was.

If the power supply was turned off AND the battery was removed (to replace it), then the PLC program would be lost.  If this is your situation, then you must have the original program (a back on PC) and programming software (I am assuming Concept, but if really old perhaps ProWORX), and you will need to download the program again.

At the very least, you will need to use the programming software to go online and check if there is anything in the CPU.

[YYK]

Thank you for the reply. 

I have checked for the associated PLC programs in the CPU, I find " .asc " files in the backup files to be the latest. But the concept is only able to upload only " .prj " files. The ".prj " files present are of older version. Can you suggest me how can I upload an " .asc " file through concept.

[MatthewM]

.asc is an export of the .prj to text file.  Use the 'Concept Converter' to import the .asc and generate a new .prj from it.

Just because the timestamp of the .asc file is newer, it does not mean it is a newer version of the program than the .prj (it just means that someone exported it more recently).  That all comes down to version control file management and you would have to compare both the establish if the .asc file is newer.