Raffaello

Ok, I got it working. Thanks for your help 

Thank for your suggestion. I want to be shure that I understand it correctly. Does  "Ladder too large" mean that the horizontal lines with the coil at the left and the output elements at the right are too long? That is, with too many output elements? So I have to split them in two lines?

I'm uploading a compressed archive containing the original files and also a screenshot of the import process and of the software showing the yellow blocks.  The original project files extensions are .cow, .dmw, .pmw and .ptw. It has been developed in 2002 using an older programming software, which one I don't know. I don't have a copy if the old programming software on any computer. Hope this may help! On my lab PC I have a GX Developer 8.45, that cannot open the old project but can import it and also download it into the plc, but something seems to go wrong during the import process and those yellow blocks show up that  prevent the PLC tu run the program.    Programma originale.rar

Hi kaare, sorry for not having opened a new post ;)  Yes, the switch is in the 'RUN' position and the green led is lit.  Actually I fear that the problem is in the conversion. The program was developed with an older software but now I only have GX Developer 8.45, which converts the old formats but -as it appears from the yellow blocks  - not properly. I think that instead of GX Developer 8.45 I should use the older software the program was developed with, but I don't know what version it was - nor how to get it. Any suggestion is welcome!

Hello, I have a related problem... hope someone may help! I have to replace an old Fx-2n 48MR. I have a (tested) new unit. In the project folder I only have  file extension .COW, .DMW, .PMW, .PT. I was able to open those files with GX Developer 8.45 by importing them. Apparently I got no errors, but some blocks of the ladder are yellow (I assume are import-related warnings).  The program loaded into the PLC without issues, but the program doesn't run. I suspect that something in the Import function does't work right, but I don't know how to go further. The guy who wrote the program is no longer available... Thanks in advance Raffaello