Sorry to post a question like this but I don't have a real firm grip on how PMEL does a limited calibration. Here is the issue we are having. We have tensiometers that have a limited cal to +/-6%, however the standard we have to reach is +/- 5 lbs. The tensiometer can read up to 400 lbs and the manufacturer specs calls out a tolerance of being able to reach +/- 4%. My question is where do they get the +/-6%, is it at a set standard on a point between 0 and 400lbs or is it through the whole range? I am trying to figure out how to get a tensiometer that can meet the requirements set for me. Thanks for any help and sorry if this is in the wrong forum.