S7-300 BF Problem

Hello everyone, friends. The S7-300 315-2PN -DP CPU I'm using gives BF per minute. Actually, PLC was working with 1 Robot - 1 Lumberg IO Module for a long time without any problems. However, I added 1 more Lumberg IO Module to the IO Module and it constantly gives CPU BF. How can I fix the problem that I think is this signal dropout? For example, is there a way to delay signal? If so, how can I do this? Would you tell? I have shared the Profibus schematic below. The Module I added later belongs to Address No. 40. I am waiting for your support for the solution. Thanks in advance.

Hi there. What is the baud rate of this network? Are you using standard Profibus cable and connectors? Did you change the terminator resistor switch to the last node? How long is the overall length of your Profibus length. I is not possible to understand what your problem is from the information provided. If you provide more data, we may be able to help.

Exactly what Alfredo posted, one added comment perhaps a faulty module

parky is of course right. Or maybe the module is not faulty but the PROFIBUS station number which is set by either rotary switch, or DIP switch or by software on the field device side does not correspond to the station number set in the configuration tool (40 as shown in the screenshot). This would also cause the BF fault.

Actually there is no problem with module addressing, because I can use Input/Outputs. However, I changed the cable in the morning and my problem was giving BF every 2-3 minutes, after changing the cable the problem started to give every 1-2 hours. Actually what I want to learn is Is there something like Signal delay. My problem appears to be electrical, The socket model I'm using is Balluff.

https://images.app.goo.gl/HepiGZDB6HRMR9pN7

So it is intermittent not constant BF.
It sounds as either a noise issue, a grounding issue, or a equipotential bonding issue.
What bus speed are you operating at ?
What distances ?
Take special care that the cable shield is properly connecting to the ground in the connector.

Are you using field-attachable M12 connectors? If so, I would recommend that instead you buy proper M12 media from makers like Turk, because assembling the M12 terminal is very difficult and I have seen many cases in which the field attachable cable is assembled without the shield, which could cause intermittent problem.
As Jesper says, please let known the baud rate, cable lengths, whether you are using bus drop-lines. And if you are using a very high baud rate, let's say 1.5 MBaud, I would recommend you consider using something slower if the process you are controlling would allow, because the slower the baud rate the longer the pulse for one bit, and thus the higher the noise inmunity.

Hello again. Thank you for your support. The cable length I use is around 5 meters. Baud Rate Profibus Properties also shows 1.5mbit (if you're talking about it). The 24V I use. DC power supply has +24 Volt and 0Volt outputs. I don't know if I should connect the shield to 0volt? Or should I make a grounding line?

The Profibus Profinet International has very good documentations on wiring guidelines for Profibus which are free of charge.
I would recommend you have a look at this information.
https://www.profibus.com/download/profibus-installation-guidelines

This is the part that I have found is not taken into account when using M12 field-attachable connectors.