7/29/2021 11:01 AM | |
Posts: 11 Rating: (1) |
Hello, Can S7-300 PLC go into STOP mode when no program change has been made and the machine worked correctly for years. OB blocks present in the program: OB1, OB85, OB86, OB100, OB122, If PLC is fine then what are possible reasons of the malfunction? On the machine making ropes I can't diagnose the reason of setting S7-300 PLC (315-2AG10-0AB0) into STOP mode while pushing the START button on the operator console and generating SF. After switching from RUN to STOP and again setting the PLC switch into RUN position the red light SF disappears and PLC works fine. The possible reasons are: - PLC fault of entering the STOP (event 4) mode and then resetting all digital outputs which may cause the problem with the spuller inverter (Simovert Masterdrive) and F008 generation (event 3) - the defected spuller inverter generating the error F008 (to small voltage on the DC link) however the voltage ~ 542 VDC doesn't change on the meter while starting the machine e.g. the fault somewhere in the DC measuring circuit. - possible problems with another DP slaves such as HV (540-560VDC) DC supplier and other problems with drives power units on the machine (capstain, braiding pipe) however not indicated with any error. The diagnostic buffer is in the attachment. (the calendar data are obsolete) Attachment20210727_Diagnose_1208.txt (251 Downloads) |