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Re: [IP] Food scale information
> Here is some additional information re: digital scales. It may be useful to
> you and others ...
Here is a description of the problem with digital scales.
The accuracy of the readout of most digital scales is directly
related to the total weight placed on the platform. If you just want
to weigh a slice of bread and it has a weight of 30 grams, the
accuracy will be very good ..... say 1% of 30 grams or 0.3 grams.
However, if you want to weigh the bread placed on a 1 pound plate,
this is where the problem lies. First you put the plate on the scale
and ask the scale to zero the reading. The plate weighs 454 grams
(remember this). The scale now reads zero. Place the bread (30 grams)
on the plate and read the weight. The answer may be inaccurate if the
scale can only resolve 1% of the weight on the scale. The total
weight is now 484 grams the error may be 4.8 grams (say 5 grams)
which is 1/6 th or 17% of the measurement. It may be high or low.
The acid test is to pick up the empty plate and place it back on the
scale, noting the new supposedly zero weight amount.
A high cost scale, capable of greater resolution, will usually not
exhibit this problem. The cheap $100-200 variety almost all suffer
this problem (at least all the ones I've checked - about a half
dozen). The mechanical Pelouze scale, can be manually adjusted to
remove this type of error almost completely.
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Insulin-Pumpers website http://www.bizsystems.com/Diabetes/
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