CPU Fault - AutoRun Program?

[jmpugh]

Hey PLCers! I am currently PLC naive, but in the process of learning more about them. At work we have a SLC 500 that whenever the power cycles the CPU Fault LED blinks and the only fix we currently have is to re-load the program and then click "run" through RSLogix 500.

My question is, is there a way to have the program we load autorun whenever the power is cycled? I also am curious, is the program getting dumped when the powercycles?

Thanks guys! I think this community is going to be very informative to join.

-- Jason

 

[curlyandshemp]

Hey PLCers! I am currently PLC naive, but in the process of learning more about them. At work we have a SLC 500 that whenever the power cycles the CPU Fault LED blinks and the only fix we currently have is to re-load the program and then click "run" through RSLogix 500.

My question is, is there a way to have the program we load autorun whenever the power is cycled? I also am curious, is the program getting dumped when the powercycles?

Thanks guys! I think this community is going to be very informative to join.

-- Jason

Is the battery OK ?
That is the purpose of it, so you don't lose the program when the power cycles

 

[jmpugh]

Is the battery OK ?
That is the purpose of it, so you don't lose the program when the power cycles

Thank you for the reply! I believe the battery is alright since the "Battery Low' LED is not lit. I ideally want to just be able to reset the PLC without having to take a laptop out to the testing station to reload the program/run the program. Is this possible?

-- Jason

 

[Paul T]

I have this same issue with a SLC 5/05, Series C FRN 9. It's 32K RAM with about 600 words left in memory; I can't do online edits on this CPU either. I have wondered if this is related to comm settings or the nearly full memory; since the machine is on the floor, I don't get to go experiment much. What's the hardware series and firmware version on yours?

 

[jmpugh]

I'll try and find out the hardware series and firmware version tomorrow and post it. The (only) laptop that has RSLogix500 isn't mine, so have to wait for the owner tomorrow. As you can see, this very reason is why it would be nice to have the program auto-run.

So one more rookie PLC question...should the program automatically autorun once the PLC is reset after a fault? I was thinking there would just be a checkbox somewhere, but is this behavior normal when a SLC 500's power cycles?

 

[mgvol]

LED's go bad; the community college I sometimes teach at has a 5/03 CPU with a non-functional fault LED. Makes some of the troubleshooting labs interesting! The next time you cycle power to the SLC, watch the LED's; all of them should blink at least once during power-up and that will tell you if the LED is still functioning. If it is, I suspect something to do with powering up or down is creating a surge, which is corrupting memory and causing the SLC to dump memory. If you can install an EEPROM in the CPU and burn the program onto the EEPROM, you can go to the Processor Status file in RSLogix500, Mem Module tab, and set the appropriate bits to have the program load from EEPROM and go to run.