S5 135/155 U Bus Fault

i am on site, i am working with S5-135U through which 3 slaves are connected . Problem is that in runing condition when all function running in Auto mode suddenly stop function and cpu shows bus Fault and light blinks for fraction fo second . to solve this problem we try a lot first we chech profibus cable and changed them but now frequency of problem is reduced but not completely solved.

So pleased sugest me what should i check for that please sir it's very important.

Problem occures ramdomly after changing profibus frequency has been reduced.

Should i check for IM module ??

Whatever is solution please suggest me....

Thanks & Regards!

Rajnish Singh

André Räppel

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