[al lkosmal]

This could be done with compression loadcells. Typically the accuracy specifications will be written something like " combined error =.2% of F.S." or something close to that. That means that the sum of all errors caused by non-linearity, hysteresis, non-repeatability, temp drift, etc. will not exceed .2% of whatever the rated load is. The tighter that error number is, the better, and typically more expensive, they are. also. look into the overload ratings. Very important, especially in an application where the load shifting, shear loads, etc. may be high while driving onto the scale, for example.

I used to be a Transducer engineer/designer and designed many strain-gage based loadcells/systems. (now I just play one in the movies.)

Regards,
Al

P.S. I have many projects going on, but I would be glad to review your loadcell selection and approach. One of the electronics engineers who worked for me, designing these weighing systems, works for me still and I'm pretty sure that he would take a look at your controller selection and make reccomendations.

P.S.S. Check out Omega catalog or website for loadcell and simple controller ideas. They are too expensive thru them, but good for ideas and then head to ebay.