Greetings,
I would like to share few tips on troubleshooting I/O cards and PLC in case of Emergency.
I has voltage / grounding problems due which S7-300 analog cards and 313C failed, replaced it with new one again it failed, later on analysing the root cause , found problem was with Electrical grounding ,
Since the plant had to be started, having sacrificed the spare too.
On opening the Analog card and checked with mutlimeter the components, found SMD fuse had blown, I soldered and brought out those two wires and connected to external fuse link outside and it worked and same also happened on S7 313C PLC ,cause all of them were out of warranty.
The similar sitauation happened in Modicon Digital input card, ,as one of the channel was accepting input, foung SMD 2.2K resistor blown , replaced it with 2.2K carbon film resistor, found working fine and it toke me 30min to troubleshoot and put that back into service.
hope this is useful, when running out of spares.
Good luck.
Jay
I would like to share few tips on troubleshooting I/O cards and PLC in case of Emergency.
I has voltage / grounding problems due which S7-300 analog cards and 313C failed, replaced it with new one again it failed, later on analysing the root cause , found problem was with Electrical grounding ,
Since the plant had to be started, having sacrificed the spare too.
On opening the Analog card and checked with mutlimeter the components, found SMD fuse had blown, I soldered and brought out those two wires and connected to external fuse link outside and it worked and same also happened on S7 313C PLC ,cause all of them were out of warranty.
The similar sitauation happened in Modicon Digital input card, ,as one of the channel was accepting input, foung SMD 2.2K resistor blown , replaced it with 2.2K carbon film resistor, found working fine and it toke me 30min to troubleshoot and put that back into service.
hope this is useful, when running out of spares.
Good luck.
Jay
