SF LED is ON on SM326 I/O module

Hi,

I have installed CPU315F with a safety protector, SM 326 DI 24 and SM 326 DO 8 I/O modules. I have downloaded the hardware configuration and CPU does not show any error. But Both the I/O modules have SF LED ON. In the module properties, diagnostic buffer shows "CRC error data message".

How can I resolve this issue? Please help.

Thanks,
Darshana K

I think the hardware configuration is not matching or check the I/O address .
Or try creating new project and upload station and then download.

Thanks for the reply, but i have checked the hardware configuration and the I/O addresses are fine. I have connected few lamps to the output channels of SM 316 DO 8 ch module. I can see flickering light through these lamps at regular interval. Is that because of the SF light or it is causing the SF LED to be ON.

what kind of interface are you using?

I am using profinet communication. and I am using ILPBs for Start, Stop and ACK commands. The lamps are connected to SM 326 DO 8ch module and the contacts (NO/NC) are connected to SM 326 DI24. Earlier SF light was ON on both modules but now it is coming only on DO module. and as I mentioned earlier, I can see flickering light at regular interval through lamps. When I open the diagnostic buffer, CRC data error message appears.

Sounds like you could have a bad connection somewhere. Im not familiar with profinet but ive been around profibus alot and you can get very strange problems if you have a bad connection somewhere.