Is this possible?

[ex_ilustre 0]

Hey there, Is it possible to turn on an indicator(LED) in siemens S7-300 using the SF error? I mean, when the SF error indicator lit(RED), this signal may also be used to turn on an indicator outside the panel that and error occurs in the PLC inside the panel. Of course, we will also consider that when SF error is lit, the CPU is in the STOP mode. This means that we cannot use the I/O's of the PLC. If this is possible, give me example program please.

[Groo 7]

The PLC stopping depends on whether the fault OB's have been programmed. There is a system block SFC51 where you can read the state of the indicator lights and from that program an output. (See SFC51 thread below)

[Groo 7]

In that case most hardware faults and any software faults will mean that the PLC will go to STOP.

[ex_ilustre 0]

oh..thank you so much for that information. Is it possible to use the status of the Stop LED, even if the PLC is in the Stop mode? Because I want to turn ON a Lamp or an indicator like LED outside a panel. The PLC is inside the panel..so when the PLC turns to Stop mode due to some errors, we don't have to open the Panel to see the STOP indicator of the PLC is lit. thank you.

[Groo 7]

No, once the PLC has stopped all outputs will be off. You could drive a relay from the PLC, ensure that the output is ON unconditionally in the PLC and supply a lampo from a normally closed ontact off the relay, therefore if the PLC stops then the relay would turn off and the lamp would go on.

[ex_ilustre 0]

hello, thank you so much for your help. I figured it out. Actually, what I wanted was to used any status of module LED..ie..SF, BATF, STOP, RUN..BUSF..etc. I already configured BATF. I used OB81, Move SSL ID(W#16#22) to MW, compare as an integer and turned ON an output address. Whenever I remove the Battery of S7-300, OB81 is called and turned ON an indicator lamp. It's enough for my project that I've used one status of module LED. I also tried to use the other Module LED's like the BUSF of profibus expansion(Im using CPU 315-2DP), but have no luck of triggering any OB's yet. Is it possible to use another OB to trigger for Bus fault(BUSF)? How do we deal with the reading of this fault? Edited 3 Jun 2009 by ex_ilustre