s7_300 cpu

[ahmed farrag]

i have 314 siemens cpu
the machine stopped and all plc output modules doesn't give any output .
i checked it and all modules are ok.
when i monitor the online program with simatic manager i noticed
the ob1 doesn't running Monitor signal ( color green which lies below window) still freeze==> can not read data.


so it reads input images but it doesn't make scanning to give the output .


is this a trick from the programmer or what ?

 

[JesperMP]

If the CPU is still running, RUN lamp is on, SF or BF are both off, but all outputs are off.
Try to force an output.
If it goes on, then you must trace in the program why the outputs do not go on.

If you have a SF or BF, even if RUN is on:
Investigate the diagnostics buffer of the CPU.
If in doubt, export it to a textfile and post it here.

 

[sigmadelta]

What is the part number of the CPU? Does it have a backup battery or a MMC (micro memory card)?

If it has a backup battery, if the red BAF light is on, change the battery. If it has an MMC, make sure it is pushed all the way in. I had a client whose big fingers happened to eject it about 1mm when trying to change the STOP/RUN switch.

 

[ahmed farrag]

If the CPU is still running, RUN lamp is on, SF or BF are both off, but all outputs are off.
Try to force an output.
If it goes on, then you must trace in the program why the outputs do not go on.

If you have a SF or BF, even if RUN is on:
Investigate the diagnostics buffer of the CPU.
If in doubt, export it to a textfile and post it here.

thank you for your reply
,the hardware diagonestic of the cpu status is ok no errors .
the error buffer doesn't contain any new errors.
as you say the cpu doesn't make any scan for inputs and doesn't gives new image of output .
i made a simple network with one i/p and one o/p but the cpu reads i/p
but it doesn't process output .

 

[L D[AR2P#0.0]]

Archive the project and post on here.

 

[Lare]

Did you try to force outputs?
If RUN led is showing run status, then it is strange if OB1 isn't running if animated.

 

[ahmed farrag]

Did you try to force outputs?
If RUN led is showing run status, then it is strange if OB1 isn't running if animated.

yes i tried to force outputs
but run led of cpu is green

 

[ahmed farrag]

Archive the project and post on here.

i will send the project to you

 

[sigmadelta]

Post a screenshot of the blocks folder of your project in Simatic Manager, and a screenshot of your OB1 monitoring online.

 

[JesperMP]

If you force an output, and it does not go on, then it does not have to do with the code in the CPU.

 

[JesperMP]

i made a simple network with one i/p and one o/p but the cpu reads i/p
but it doesn't process output .

That is not forcing.

 

[pacotabaco]

Did you changed hardware config? Or the did the cpu stopped working suddenly?

What colours are the cpus leds? Are all them blink?

Check the IO addresses on hardware module config are the same addresses that you are using in ob1

 

[jvdcande]

Maybe a foolish question, but did you check the power supply for the output cards?