sded has me thinking to recheck alignment. There is no fore and aft adjustment with the bracket and the balmar is a tight fit on the legs. Perhaps I have a similar problem and will need to file or grind down the bracket to allow some adjustment with shims. I'm doing some work in that area and will recheck alignment.

I'm not sure if the ramp up can be adjusted on the Xantrex but I'll take a look. I tried cutting back the output and that helped a bit.

The problem is two fold. Under the full charge, I was getting a slipping that actually lacerated an area of the belt. Hard to tell which pulley, engine or alternator (WP I would think would just spin) was cutting it. It was always on the front face which makes me think alignment, again. That seems severe, I know. The belt is actually stopping momentarily....

I did have trouble adjusting belts (I went through several last season on a cruise where battery charging was really tested. I was overtightening at one point I think. I'll take your advice on getting and adjustment tool.