Troubleshooting Siemens HMI w/Step 7, & WinCC/Redlion HMI question

Tomorrow morning I have to use a rented Siemens PC to troubleshoot a Siemens HMI, programmed with WinCC, communicating to a couple of ABB drives over Profibus. The rented Siemens PC with has Step 7 on it, as well as WinCC flexible advanced.

This is what I experienced today:

1. Values entered on the HMI "entry screen" were not writing to the ABB drives. We know this because those values would normally show up on the "main screen".

2. The "main screen" has graphics that normally open up the "entry screen" when touched. These are not working, while other links to the "entry screen" still work.

3. The ABB ACS800 drives have a RPBA-01 Profibus Adapter, linking them to the HMI. There are four indicator lights. The "on-line" light is blinking green, and the "off-line" light is off. The problem is, the manual doesn't have a "blinking light" option or "on-line". ABB Tech Help doesn't know why it's blinking.

So, at this point, it looks like there are three possibilities:

1. I have a communication issue between the HMI and the drives.
2. The HMI program file is corrupt.
3. The HMI is bad.

Complicating factors:

The customer can not find the flashdrive with the original project. He does have a paper printout of the project to use for reference.

I've only used Step 7 one time before to troubleshoot an S7-300, with phone help.

I'm hoping to use this laptop with Step 7 tomorrow to look for faults. There is a chance that the HMI will need to be replaced. Since I don't have a back-up project file, I'm thinking I may need to re-create the HMI from scratch. I don't program HMIs very often, but when I do I like to use the RedLion HMIs.

So my questions are:

1. Does anyone know why the "on-line" indicator light is blinking?
2. Can I diagnose the Profibus network just by plugging in the pass-through cable on the back of the HMI and choosing: PLC -> PROFIBUS -> Diagnose, Monitor/Modify Node in Step 7 (SIMATIC Manager)?
3. If the HMI needs replacing, what is your opinion about switching to the RedLion HMI since I don't have the original project file. ...I don't know what I don't know, since this is not the type of thing I do everyday. I suspect I'll find the correct drivers for the PROFIBUS network, through the 9-pin D serial connector in the RedLion software. I'm a little fuzzy about mapping the drive addresses... any words of caution or encouragement are appreciated.

There might be more questions tomorrow. These are just the ones I'm pondering tonight as I download manuals and such.

I would imagine it's less complicated than what you think. It sounds more likely that the plc isn't in ruin mode or there is a device on the profibus that is no longer passing communications.
My experience would say to verify run mode then
Get online with the plc and go to the diagnostic buffer it should tell you what it can't find on the bus.

1. to check if it in run mode: It will be under hardware config and then under plc... either operating mode, or plc mode. I forget currently don't have one running working on other brand.

2. diagnose the Profibus: Under hardware config, click on the go online icon. It will be red if NOK and green check box if ok. If two profibus lines are going into the comm make sure the switch is in the off position if only 1 is going into (make sure also only into) check and make sure the switch is in the on position.

3.HMI needs replacing: Sorry i can not help there I have not seen an HMI that ever needed to be replaced.

also the hmi and the plc are different endians so be aware of this you will have to byteswap.

Here's what we learned today....

The system was working today, so I hooked up the laptop to see what I could learn about the issues yesterday

1. It was good practice for me to hook up the HMI to the laptop, and then use the diagnostic functions of Step 7. I didn't have the project to load, so this was pure exploring of the diagnostic functions on the Profibus network and the HMI/PLC.

2. They were using WinAC as a "soft" PLC... meaning it's a PLC program running on the HMI operating system. (Right?)

3. I was able to upload the project as Profibus nodes into Step 7. I don't remember the commands, but first I chose to diagnose the Profibus network.... then I established communications with the bottom menu item under "Options".... PG/P???? (I was "trying" things and didn't write this part down) The part I did write down: Select the profibus master under the "Access Nodes", which was Profibus= 4. Then, under PLC menu, Diagnostics Set..., then Hardware Diag.... then, push the "Module Info." button. Then I got to see the "____ Buffer", which has the system events.

4. The item that stood out was "Distributed I/O Station Failure". The PLC called for an error-handling file, OB86, and since the file did not exist, the PLC entered Stop Mode.

5. Note for future: The "On-line" indicator lights on the slave nodes blink green when communications are established, but the PLC is in Stop Mode. ....My understanding is that without a OB86 file, you need to restart the PLC to clear the fault. My adviser today said I should find a way to load an empty "block" file labeled OB86. Then, the PLC would continue functioning, once the issue went away, without a re-start.

BTW... you guys called the Run/Stop Mode causing the blinking lights! Nice.

6. I still don't know what caused the Distributed I/O Station failure.... which would be nice to know. I had the same issue last Friday at another customer, but they actually had a remote I/O rack with a visibly bad card. This system today just has three ABB drives, connected by Profibus network. There were some Log base addresses involved... "slave input address 8188", and under that a "master" address of 8191. Maybe that tells me where the problem is, but I don't have the original project file available, at least not yet. Any advice on how to figure out those addresses?

7. The HMI model is: 6AV6 644-0AA01-2AX0... which is discontinued, but still available. The screen has frozen up on them a couple of times lately, and we suspect the HMI might have "issues". They also have a few "dead" spots on the screen from high-use areas. If they can't find the original project files, the thought is that we could do a back-up/restore to put the system onto a new HMI. I hate putting that kind of money into a discontinued/legacy HMI, but it seems like it would be the easiest and probably the cheapest solution at this point. What do you think about this?

9. I want to learn more about the soft PLC, WinAC, so I'll be looking at the manual. Here is the link if anyone else wants it.... http://support.automation.siemens.c...lib.csinfo&lang=en&objid=26729818&caller=view

That's about all for now. I'll be hearing back from the customer once they see if the original project engineer gets a chance to check his archives for the original project files, next week. Then, we'll discuss whether we want to replace his HMI or not.

I added a lot of detail in this response so others could reference it. But since I'm still learning about the Siemens world, I'm hoping to add to my experiences with advice from those of you who have more knowledge. Feel free to elaborate on anything you think I should know. I've had 2 Siemens PLC issues in the last week, and I'm scheduled to do another tomorrow. Again, I'll be using the rented laptop with Step 7 to diagnose a fault light on a S7-300.

to view what is causing the fault, go to the plc under the hardware in step 7 and it's either module information or plc operating mode. sorry I cannot verify this, I currently do not have a siemens plc running. Should be under a tab in one or the other under diagnostics I think.

Ob86 is required for a rack fault. Go to blocks and right click, insert new object, Operating Blocks and type in OB86 and download it. it makes a siemens block that will take care of this fault to keep the system running.

I have not used WinAC sorry can't help you there.

Your understanding of OB86 in §5 is not quite correct. If you install an empty OB86 then the program will ignore the fault and keep running regardless - you want to be sure that this is acceptable before going down this route. Also, when the CPU goes into stop after a fault then you can use the diagnostic buffer to follow the program to the exact position where the fault occurred.

You can find the diagnostic addresses you refer to in §6 (8xxx) in the Hardware Config, clicking on an object on the Profibus line and in the table below you'll find the diagnostic address for all the cards or objects concerned.