Siemens s-7 400 Problem

AA,

I am sorry I do not have a direct answer to this one ..BUT if you want to keep this in virtual text form

Have you tried the Siemens Tech Assist and FAQ link @:

https://support.automation.siemens.com/WW/llisapi.dll?func=cslib.csinfo&lang=en&objid=38718979&caller=view

or

http://tinyurl.com/27n86oz

From the link there is access to a human if the FAQs fail to take care of the issue..

Or you could call 1-800-333-7421 and have a engineer give you a call back...

Siemens is usually pretty good about the after sales service and support..

Cheers and good luck,

Eric

hmmmm interesting fault i have experienced some what like the same fault at my plant, you don't have to reload all configuration althoug you have done it now its good. all your CP's are connected with your CPU by profibus, all you have to do is check every thing loop by loop it means start from the cpu's profibus connector turn in On then move to the next card atached to in series and turn its switch ON then turn the CPU switch OFF then move to the third one and turn its connector switch ON and turn the second one OFF. in this manner loop check all your attached cps and CPU's more than one person working simultaneuously cordinating each other.This will resolve your BF and SF.tell me if you understand what i am telling you to do and if you don't then we will have to talk on phone.

Hi there,

Firstly, on the CPU the EXTF led indicates external fault. This means that one of your field devices has fallen over i.e. is not reachable.

The INTF led indicates internal fault. This is software related. You will more likely than not find that in the software they are using the following statement L PIW xxx. This means go directly to the device to get the data instead of reading the PLC input image.

On the ET station BF - bus fault. This means that the device is not being read on the bus. This could be a faulty IM module, or someone has played with your terminating resistors. Make sure only the first terminating resistor and the last terminating resistor are on.

The SF led means that there is a signal fault. This means that one or more of your analogue circuits on that station has gone open ciruit, or one or more of our instruments on that station have failed.

What you should do now, is to switch the power off to the stopped CPU rack. Leave it off for a minute of two. Then switch the power on. If I remember correctly, this will force the now standby PLC to read the master PLC's hardware configuration etc and start up with the same data as the master. (refer to the H CPU documentation in Simatic Manager to make sure)

You can then fault find from there.

Remember this with Siemens - never download unless you have made hardware changes. Those red LED's signal hardware i.e. device faults. These are things that you have to sort out in the field.

The standby PLC will not start as it is now, because it has a different configuration to what the master has. It will start up when you force it to load the masters configuration with the power recycle.

Keep us posted and let us know what you find.

Regards,

Craig