PLC 5000 faults programming

I'm new to plc programing and any help will be appreciated. I'm working with Allen Bradley 1769-L32E with panel view plus 7. I need to somehow be able to read and clear faults from the plc via the panelview. I see Local:1:I:Faults on the control tag menu of the plc but I'm not sure if that's all I need to read and clear faults. any help will be greatly appreciated. Thanks.

please explain your program a little better.
the machine is running,
you see inputs that causes a fault
explain your code that sets the fault.
what do you need to do when you clear the fault?
how to reset the machine to start the process over?


james

Yes please explain, are you talking about faults that may occur in the PLC hardware or faults generated from the machine you are controlling.
For example Faults like I/O cards not talking on the bus, PLC error codes etc. or are you talking about process faults like Motor O/L, Solenoid failed to reach open etc. It would help to know what types of faults.

So the only thing we can tell you from what you posted is that you are looking at faults associated with the card located in slot 1 of your local rack. I doubt you can reset any faults from there but you may be able to display some useful information from that fault word. As mentioned by other posters, you will need to fill in more information to allow us to help.

kojoalmighty said:

I'm new to plc programing and any help will be appreciated. I'm working with Allen Bradley 1769-L32E with panel view plus 7. I need to somehow be able to read and clear faults from the plc via the panelview. I see Local:1:I:Faults on the control tag menu of the plc but I'm not sure if that's all I need to read and clear faults. any help will be greatly appreciated. Thanks.

Click to expand...

Let's say Local:1:I:Faults is your Carbon Monoxide alarm, it went off, now you just want to 'clear fault' without finding what caused that alarm?
Do you want to unplug it go to bed and call it 'I cleared the fault?"

And I would also say to clarify what you mean by fault. I usually use the term "Fault" to indicate a problem within the PLC. I use "Alarm" to indicate a problem in the process.

For example:

• The battery in the processor has gone bad and that has caused a minor fault in the PLC.
• The temperature level in a tank went above the high limit and caused an alarm.

FYI, in the PLC, there are Major faults that cause the PLC to shutdown, and Minor faults that are cause for concern but do not immediately result in a shutdown.

Ideally in the PLC we write fault logic that captures the major fault condition, clears the fault to prevent a shutdown, and then stops the process. Then, once the process is confirmed to have shutdown, the logic may stop clearing the fault and allow the PLC to shutdown.

That is not universal. Many systems just immediately shutdown. Orderly shutdown versus slamming to a stop.

OG

kojoalmighty said:

I'm new to plc programing and any help will be appreciated. I'm working with Allen Bradley 1769-L32E with panel view plus 7. I need to somehow be able to read and clear faults from the plc via the panelview. I see Local:1:I:Faults on the control tag menu of the plc but I'm not sure if that's all I need to read and clear faults. any help will be greatly appreciated. Thanks.

Click to expand...

Hi, and welcome to the forum. I am able to only presume, as the other pros on here have written, that perhaps you are looking for fault status from a particular input card. When you expand the "Fault" section of "Local:1:I, you see that it is a DINT. So one could assign say, Local:1:I.Fault.0 to a tag that could be connected to the HMI. That at least would give an alarm on the HMI that the particular input card has a problem. I may be off in the weeds a little here, if so my apologies to all, but that's one way.
If you want an alarm as mentioned above, the Local:1:I.Data.1 for instance could be used in logic (pressure switch, sensor, estop) and if that bit is or isn't true for some reason, however you write it, then that tag could be mapped to a connection in the HMI, which could be used to set an alarm banner. Hope this helps

I'm confused by your message too. Are you perhaps getting the PanelView alarm screen faults confused with processor and IO status and fault messages? Depending on the device, normally the fault message queues in hardware will always be there as a history. The only other hardware faults you will have are major faults that shut stuff down and either go away after the fault or end up in the history.

As for Panelview faults on alarms screens, 99% of the time these are process faults you have programmed to latch on in the program and that you can acknowledge and reset from the PanelView.

So which is it and give a specific example of what you are going through from the processor to the PanelView please.

Let me hijack this thread a little bit to ask about issues we had with ControlLogix 1756-L82E PLCs and some of modules.

So we had modules stopping communication with CPU. It happened 3 times so far, twice for AMCI SSI card where we caught error code 16#203 pointing out it was communication failure on backplane. We figured out most likely it was happening as our RPI time was 0.5 ms. Later we increased to 2ms. We cannot go slower than this for this process. Module stayed in fault for few seconds before it continued to work.
3rd one was for fast analog input/output card 1756-IF4FXOF2F/B, where we didn't catch an error. Here module stayed in error until client reset it before catching an error code.

So we started adding logic to check the health of the modules and do some appropriate actions based on diagnostics.

My question is does anyone have idea why it might be happening and what is your experience about A-B PLCs having problems like this? I've never experienced something similar with Siemens PLCs, where I have more experience.
Do you usually put module fault handling in your programs? Any tips here for novices like me, who are doing first project with A-B PLCs?