Dear Experts,

Today I encounter very strange thing with our cement plant CPU 410-5H.
The operator report that he has loose process control from all tags on wincc.

I start Checking the Operating Mode from CPU -> PLC -> Operating mode and the message came that the CPU can not be accessible from ES (Engineering Station) 

I decide to check the PLC and found that all the LED on the CPU start from INTF, EXTF, BUSxF, MAINT, IFMxF, RUN, and STOP are Flashing and all the CP's (2 Ethernet, 2 Profibus) are in STOP mode

I tried to switch Off the CPU and Switch it On 

The LEDs were not flashing at this moment but the Stop LED was Flashing 2 Hz

I waited for sometime but The CPU was not Restarting.

I decide to Perform "Resetting the CPU410-5H to factory settings" and wait for the CPU to restart and It was Successful.

I load HW config. and Entire CFC download then Everything back to normal.

My Questions?

1. What may be the Causes of such scenerio?

2. Will this event have impact to CPU and may this reapeat?

3. What measure should I take to prevent this from happening again?

Thank you.

Hello,

maybe first step is check diagnostic buffer of CPU for events, date/time and check some interesting records what can point you to what was happened.

 Hi,

U must share diagnostics buffer log of that period.

1. What may be the Causes of such scenerio?- There may be CPU-CPU changeover & diagnostics functions are running on ES.

2. Will this event have impact to CPU and may this repeat?- No. 

3. What measure should I take to prevent this from happening again?- Avoid diagnostics functions running contineously on ES- e.g. Force, Monitor, HW/Netpro activate etc. 

Mbab05

Dear Experts,

Today I encounter very strange thing with our cement plant CPU 410-5H.
The operator report that he has loose process control from all tags on wincc.

I start Checking the Operating Mode from CPU -> PLC -> Operating mode and the message came that the CPU can not be accessible from ES (Engineering Station) 

I decide to check the PLC and found that all the LED on the CPU start from INTF, EXTF, BUSxF, MAINT, IFMxF, RUN, and STOP are Flashing and all the CP's (2 Ethernet, 2 Profibus) are in STOP mode

I tried to switch Off the CPU and Switch it On 

The LEDs were not flashing at this moment but the Stop LED was Flashing 2 Hz

I waited for sometime but The CPU was not Restarting.

I decide to Perform "Resetting the CPU410-5H to factory settings" and wait for the CPU to restart and It was Successful.

I load HW config. and Entire CFC download then Everything back to normal.

My Questions?

1. What may be the Causes of such scenerio?

2. Will this event have impact to CPU and may this reapeat?

3. What measure should I take to prevent this from happening again?

Thank you.