Siemens S5 135U - CPU 928B - iStack help - ADF FLT

Hello everybody,

Today I am facing a problem with S5 PLC 135U. As in topic I am attaching iStack screens. I am not so familiar with S5 diagnostic, would somebody could tell me which peripherial remote IO (address) seems to be fualty?

Basically we are having problems while we are powering up a machine. After few seconds PLC is going into stop mode and ADF and BASP LEDS are constant ON and RED, STOP is blinking red slowly. After few minutes stop/start from CPU switch is helping and machine is ready to work. 

From what I've read on forum, I am assuming that machine may have problem with one of the remote IO.

CPU have cards: 2x 6ES5 432-4UA12, 2x6ES5 451-4UA12, 1x6ES5 470-4UA12 and communication module : 6ES5 308-3UC11. and 13 ET200B Remote I/O

Correct me if I am wrong, but I am assuming that ADF fault is coming from OP-REG: 53AC - Instruction T IW/QW 172 ? So probably I am having issue with remote IO which cover address 172? Do I think correctly? 

I would appreciate if somebody would explain me more attached iStack and possible causes of stop and also correct me if I am wrong.

ADF LED

So, you are on the right path.  I think your instruction is T PW 172, which means it's an output module with address 172.  If it was L PW 172, then it would be an input module.  L means load, and the P address is an input address.  T means Transfer, and the P address is an output address.

Thank you for your quick answer, Thats what I thought. 

Now It's strange cause from electrical documentation address 172 is an Analog input assigned to remote IO :

ET200B 8AE - ET 200B Electronic Module Analog, 8/4AE - 6ES7 134-0KH01-0XB0 

Card has PW from 160-174

I will double check this card on Thursday to be sure that schemes matching reality. 

If its analog input module then the instruction Transfer to Analog Input 172 seems stupid. 

Is it possible that that the card is configured for 4 AI so the second byte don't exist ? 

Update :

From Electrical drawings it looks like all Inputs are used with two wires sensors (voltage sensor perhaps) 

I will try to replace pointed module and then I will see if that help. 

Your S5 rack has an IM308-C Profibus module. It's best to get the COM ET200 or COM Profibus configuration file.  I have seen discrepancies between the configuration file and electrical drawings.

The instruction T PW 172 is *definitely* for an output module/channel.  It's not possible to transfer to an analog input.