Hello,

I am new with siemens,

I have cpu 317 and 4 racks with im-153 (profibus)

Some times every 2-3 days the forth rack didn't show any i/p or op for one second only then back again to normal.

We concentrate monitorg on cpu bf and found that it illuminate for one second then go off!!!

We check tighten for profibus cables connector and check for all racks led, all seems normal.

The cpu is password protected.

Any suggestion please, as for now this problem repeated 5 to 7 times / day. 

hello,

could you send the diagnostic buffer?

thaks you

Thanks for reply ,

I manage to access CPU and attached the diagnostic buffer (attached).

It shows the issue happend for msec.

I donot know if this issue related to profibus or for 24 v supply of this rack.

Thanks for support

Hello,

There is a problem connecting one or more remote I/O

like mopS04 already mentioned you would check this device for proper shielding and grounding