Dear user,

PLC going to STOP mode and it starts if i restart by using Manual Reset,

Again after 2 or 3 hrs again it is going to STOP Mode.

As per Diagnostic Buffer it shows below mentioned error,

CPU MODEL:6ES7412-5HK06-0AB0

Event 15 of 120:  Event ID 16# 457F

STOP caused by STOP command

Breakpoint in user program: Cyclic interrupt OB (OB  35)

Priority class:   12

FB number:     49

Module address:  10694

Previous operating mode: RUN

Requested operating mode: STOP (internal)

Event occurred in the master CPU in rack 0

Internal error, Incoming event

12:46:16.414 PM  06/27/2025

(Coding: 16# 457F  F884  8E70  0C23  0031  29C6)

Event ID 16# 457F is STOP  due to SFC46. Please tell us more about FB49 and see why the module STOP command is triggered. This is a behavior ,I encountered in the  blocks from the older S7-F/FH Systems libraries.

Kind regards,

hdhosseini