First of all this web site has been helpful as far as getting me to were i'm at with this problem. Thanks!!!! Here is were I'm at we have s5 922 cpu. I can not get the cpu to go to run. We have had an engineer in here and hasn't been to successful. in the Istack we originally had fe-stp and Bau. In the power supply we disabled the jumper to look for battery then we got a ob1 fault. I replaced the battery and got the mb led to go away and reinstalled the jumper. I am now noticing that upon resetting the cpu the green run light will flicker than go back to flashing red stop. We also Have a eprom and another piece of equipment with same plc set up we have taken the cpu and installed it on the other rollstand and it loads fine.Any suggestion and sorry for the length tried to give as much detail as possible
s5 help!!!!
- Thread starter quebmaint
- Start date
Quote: "the green run light will flicker than go back to flashing red"
Sounds like the program is faulting. This is usually due to the state of the inputs or a math-overlow error in the program.
I would compare the state of the machine to the one that does work.
Are there any encoders that may have travelled too far and the program can't handle the input?
Do you have any ethernet devices that may be sending corrupted or non-standard data?
Try isolating the PLC by turning off of disconnecting as many of the external devices as you can.
Without further information about the machine, that is my best guess.
Sounds like the program is faulting. This is usually due to the state of the inputs or a math-overlow error in the program.
I would compare the state of the machine to the one that does work.
Are there any encoders that may have travelled too far and the program can't handle the input?
Do you have any ethernet devices that may be sending corrupted or non-standard data?
Try isolating the PLC by turning off of disconnecting as many of the external devices as you can.
Without further information about the machine, that is my best guess.
If the programmer wrote the program to clear all data on the first pass, then it would. This is not common, most likely it does not.
Is this a small machine, big machine, what are we dealing with?
What led up to this problem?
Do you have the software/hardware/knowledge to go 'online' with the processor?
Is this a small machine, big machine, what are we dealing with?
What led up to this problem?
Do you have the software/hardware/knowledge to go 'online' with the processor?
its a rollstand pretty big machine. What led up to the problem we had a gear box go out on the turret they shut the power off to replace the gearbox/motor. And when power was turned back on the cpu faulted and the switch was broken off the run/stop.So the electrican took a cpu off of the other equipment and got the cpu to reset. The machine ran for a couple of hours that I'm aware of and lost functions (fault)
We have had a engineer in working with us that is not familiar with s5 he can however get online and check the I stack which showed us the fault mentioned before, after clearing that fault we got db1 or ob1 not sure now its been a long night sorry. so to answere your last question not really
We have had a engineer in working with us that is not familiar with s5 he can however get online and check the I stack which showed us the fault mentioned before, after clearing that fault we got db1 or ob1 not sure now its been a long night sorry. so to answere your last question not really
More of an Allen-Bradley guy myself.... Hopefully one of the Siemens experts will chime in soon.
Considering that it ran for awhile and then faulted again still leads me back to a bad input. Something outside of the PLC. Possibly an encoder or sensor on the turret???
Is there adequate power at the PLC? Maybe the feed to the PLC is shorting out somewhere and the fault is being caused by low power.
Considering that it ran for awhile and then faulted again still leads me back to a bad input. Something outside of the PLC. Possibly an encoder or sensor on the turret???
Is there adequate power at the PLC? Maybe the feed to the PLC is shorting out somewhere and the fault is being caused by low power.
moggie
Lifetime Supporting Member
Have you looked at the IStack and BStack to see what fault exists now that the mb fault is clear?
Have you tried a cold restart?
Is the program held on RAM or EProm?
Have you reloaded DB1
Have you tried a cold restart?
Is the program held on RAM or EProm?
Have you reloaded DB1
Last edited:
Let me see if I undersatnd this right. The roll stand went down for mechanical repairs, when starting back up the cpu had faulted, the reset switch was broken off and the cpu could not be reset. That cpu was removed and another was installed in it's place. Roll stand ran o.k. for a few hours and then the new cpu faulted to. Does this sound about right?
I have a couple of questions. Bare in mind I'm no S5 expert and have only been around the 928's
1. Does anyone know why the first cpu faulted?
2. Does your program run off RAM or EPROM?
3. Did you swap RAM/EPROM when you swapped CPU?
4. Would you consider the red STOP led to be flashing rapidly or slowly?
5. Are any of the other error led's on.
6. Did the roll stand actually run for a few hours or did it just sit idle for a while with the cpu run light on.
I have a couple of questions. Bare in mind I'm no S5 expert and have only been around the 928's
1. Does anyone know why the first cpu faulted?
2. Does your program run off RAM or EPROM?
3. Did you swap RAM/EPROM when you swapped CPU?
4. Would you consider the red STOP led to be flashing rapidly or slowly?
5. Are any of the other error led's on.
6. Did the roll stand actually run for a few hours or did it just sit idle for a while with the cpu run light on.
1.no
2.eprom
3.took cpu out of one machine with that machines eprom
4.it has blinked fast and slow depending on which type of reset is being done
5.just the bottom led that bsp i believe that tells you the cpu has stopped outputs
6.That one i'm guessing on wasn't there when it happened but I think they said it was running then the brakes locked up and lost all functions.Which is the result of the plc fault.
2.eprom
3.took cpu out of one machine with that machines eprom
4.it has blinked fast and slow depending on which type of reset is being done
5.just the bottom led that bsp i believe that tells you the cpu has stopped outputs
6.That one i'm guessing on wasn't there when it happened but I think they said it was running then the brakes locked up and lost all functions.Which is the result of the plc fault.
as to moggie's ?'s its a eprom. We had a eprom burnt and we replaced it.I can't say for certain what IStack fault we are getting when we took off the jumper mm-mn in the powersupply we got what db1-fe Not a 100% sure The engineer said he thought that was because we opened the jumper.I have my doubts.
moggie
Lifetime Supporting Member
DB1-FE indicates an error with DB1, either it is not programed or its structure is not correct.
DB1 is a list of I/O
You need to go on line and check DB1 exists and if it does, that it is correct. Also check the IStack and BStack.
DB1 is a list of I/O
You need to go on line and check DB1 exists and if it does, that it is correct. Also check the IStack and BStack.
One thing you can do to check if its the CPU itself or the program is to delete the program from the PLC using STEP 5 (programing software for S5).
In STEP 5 you go to menu File-->Blocks-->Delete enter. In the Delete block(s) menu choose PLC as delete source and under Selection choose "Delete entire PLC" and enter.
After youve cleared the PLC this way start the CPU and see if its okay, if it is you got something wrong in the code or the CPU doesnt support something in the code.
Even though the CPU has the same name the versions can differ from eachother.
If nothing happens you might have a hardware error. Maybe some I/Os doesnt work or the code is trying to read I/Os that arent in use.
Can you extract the program from the old CPU? It might have been changed without updating the EEPROM.
This is something to start with atleast
In STEP 5 you go to menu File-->Blocks-->Delete enter. In the Delete block(s) menu choose PLC as delete source and under Selection choose "Delete entire PLC" and enter.
After youve cleared the PLC this way start the CPU and see if its okay, if it is you got something wrong in the code or the CPU doesnt support something in the code.
Even though the CPU has the same name the versions can differ from eachother.
If nothing happens you might have a hardware error. Maybe some I/Os doesnt work or the code is trying to read I/Os that arent in use.
Can you extract the program from the old CPU? It might have been changed without updating the EEPROM.
This is something to start with atleast
Oh yeah just remembered that you can check if its something in the program quite easily.
In OB1 use the code :BE (block end) to stop the CALLs or JUs (jumps) to eliminate sections of the program. That way if its in the code you can zero in on where the problem might be.
In OB1 use the code :BE (block end) to stop the CALLs or JUs (jumps) to eliminate sections of the program. That way if its in the code you can zero in on where the problem might be.
moggie
Lifetime Supporting Member
Have you fixed the problem?
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