During a recent job, we encountered a T03:C20 fault when powering up the PLC. According to Rockwell literature, this fault is deemed unrecoverable. Despite replacing the rack (chassis) with a new one, the error persists. As someone new to PLC components, I am unsure if the CPU module could be the root cause of the issue. Could it be related to the program loaded by the customer? I have 18 years of experience as an electrician, dealing with various terminated PLCs, and while I understand I/O, programming is not my forte. Any assistance in troubleshooting this issue would be greatly appreciated.
Are you still encountering the same error even after changing the chassis? Typically, a major non-recoverable fault will cause the program to be dumped. This means that unless you reload the program into the CPU, you will continue to see the message about the original fault even if the root cause has been addressed. Based on the error code, it appears to be a hardware issue, as nothing in the user program should be triggering it. It's worth noting that there is no such thing as a MicroLogix 5000; based on the error code and the presence of a chassis (the rack for cards), it seems likely that you are using a ControlLogix system. If the error persists after reloading the program, it may be worth investigating the CPU as a potential culprit, such as a damaged pin or a poor connection to the chassis.
From what you've shared, it does indeed seem like a complex issue. Yes, typically a T03:C20 fault is indicative of a potentially catastrophic fault with the PLC. However, do note that sometimes, the error might not lie with the hardware itself but could be associated with the PLC programming or configuration, especially if the error persists even after changing the hardware. Thus, you might be onto something when you suggest that the program loaded by the customer could be at fault. Perhaps getting a programmer to look over the PLC program might shed some light on the issue. Also, while I understand programming isn't your strongest suit, learning basic troubleshooting of PLC programs might be a useful skill to acquire for future incidents.
From what you've shared, it does indeed sound like a very complex issue. I've encountered a similar problem in the past, and in my experience, while a T03:C20 error usually means that there's a hardware fault that cannot be addressed via programming changes, it doesn't necessarily mean that the CPU is the culprit. It might be worthwhile to also examine the power supply or other key components. Since you've already replaced the rack with no success, you might also want to look at the backplane. As for the programming aspect, I'd suggest reaching out to the customer to verify if any recent changes were made just to rule out any software-related discrepancies. It's always better to examine all possibilities before zeroing in on one cause. Hope this helps and good luck with troubleshooting!
It sounds frustrating to deal with the T03:C20 fault, especially since you've already swapped out the chassis. From what you've described, it could definitely be a CPU issue, particularly if the fault is persisting despite the hardware change. Have you checked the CPU for any signs of damage or potential misconfigurations? Also, it's worth considering that sometimes, issues within the program itself can trigger faults if there are compatibility problems or bugs. If you haven't already, try loading a known good program to see if the fault clears up. It might also be helpful to reach out to Rockwell support for more insights specific to this error code. Good luck!
It sounds like you're dealing with a tough problem, especially if the fault persists after replacing the rack. Given that the T03:C20 fault is typically related to non-recoverable hardware issues, the CPU module could very well be the culprit if it’s also damaged or improperly configured. It would be worth checking if the CPU is correctly seated and if there are any visible signs of damage. As for the program, if it was created with settings inappropriate for the new hardware or if it’s corrupted, that could definitely cause issues during startup. You might consider trying to load a default program or factory settings to see if the error clears up; testing with a known-good backup could also help isolate the problem. Good luck!
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Answer: - The T03:C20 fault in a Micrologix 5000 PLC is considered unrecoverable according to Rockwell literature, indicating a serious issue with the chassis or other components.
Answer: - If the T03:C20 fault remains even after replacing the chassis, the issue may be related to other components such as the CPU module or the program loaded onto the PLC.
Answer: - Yes, the CPU module could potentially be the root cause of the T03:C20 fault. It's advisable to inspect and test the CPU module as part of the troubleshooting process.
Answer: - It's possible that the program loaded onto the PLC could be related to the T03:C20 fault. Reviewing and analyzing the program code may help identify any issues contributing to the fault.
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