corrosion on a cable will do it as well. There may be an underground splice if it is underground. Make sure you aren't bucking power. I have seen power buck and not blow the fuse. One of the legs may have an le or amp that is drawing more than it should. The mod in the PS may be haveing a problem. Are you seeing an increase in amp draw when you fuse the leg? I am going with a bad mod in the ps. That is what happened in Kodiak. One leg kept going to 47 volts and it was the power supply. Also a PI may be burnt. look for that on one leg of the pi. There are many things to cause this. sorry
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