Kjetil Posted March 26, 2012 Report Posted March 26, 2012 Hi folks! I'm writing a program in GX IEC Developer for my Mitsu FX3U-16M. My program is built up by both LD and ST. All my LD programming, and simple IF- and CASE-executions in ST are working perfectly. The only thing that is not working is loops, I've tried WHILE, FOR and REPEAT. All of them are recognized in GX IEC Developer, when pressing the 'build'-button I have no errors or warnings. But after I've uploaded them to the PLC, and I'm testing the program, the error-lamp on the PLC is lit, and nothing works. So, are there some settings that has to be done in order to make loops work? Thx, Kjetil Quote
kaare_t Posted March 26, 2012 Report Posted March 26, 2012 I noticed you haven't read out the error code, but since your doing looping my first guess would be that you have an infinate, or simliar, loop which causes the PLC to go into error. The PLC has a default WDT of 200ms checking if scan time is too high. You can adjust the WDT in D8000 if I remember correctly. Alternatively you can use the WDT_M instruction to reset the WDT during run (each time the WDT instruction is triggered the WDT will reset to 0). However in any case you should check your loops to avoid high scan times. Quote
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