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  4. Zeroing problem and ratio problem

Zeroing problem and ratio problem

JPL's picture
Submitted by JPL on Mon, 04/27/2015 - 8:14pm
Topic Type: 
Question

I noticed sometimes when I zero the scale and have something on it that it will sometimes take a portion of that weight and zero it as well. Is that just a weird fluke or have you noticed this too? Also, I found that sometimes when the weight is shifted on the deck a little that it activates the ratioBlownOut function and it won't go away

Trenton's picture
Submitted by Trenton on Tue, 04/28/2015 - 6:38pm

JPL, first of all it is gratifying to me that you actually built the device from my instructions. Regarding your question, I also found the scale does not hold absolutely on 0, but I assumed it was the error inherent in the pressure transducers I used. I think my pressure transducers are 500 psi 1% FS error where maybe I should have used 300 psi to reduce the error. In actual practice by weighing cattle and then seeing the official weight at the sale barn I believe my device is accurate to about 7 lbs, but the weights on my ticket at the sale always are multiples of 5.

I don't think I've had the problem with shifting weight, but you can adjust the ratio in the function if you like. I seem to recall in course of design and testing I felt like I did revise it toward a more permissive ratio, but I suppose you could take it further based on experience.