Usually strain gaged loadcells have very small deflections. So movement
sticking is unlikely to be an issue.

Software issue may relate to low cost analog to digital conversion, reading
frequency, etc.

"Dave Gibson" > wrote in message
...
>
> "Farry" > wrote in message
> ...
> > Dave Fawthrop > wrote:
> >
> > >On Sun, 25 Jan 2004 10:38:41 GMT, Farry
> > > wrote:
> > >
> > >| Dave Fawthrop > wrote:
> > >|
> > >| >I use the Salter electronic Aquatronic model number 3007, all
plastic,
> and
> > >| >find it everything I had hoped. I have checked the accuracy a few
> times
> > >| >and found it fine.
> > >|
> > >| I would also have said that, but of the scale I bought a year ago,
> > >| rather than the "compensated" scale. When did you buy yours?
> > >
> > >Sounds as if yours has a simple mechanical fault. Perhaps crud has
built
> up
> > >inside, or the platform has got twisted.
> > >
> > >I have had mine about ?2? years.
> > >
> > >I have just tried adding sugar slowly, no problem.
> >
> > OK, the model 3007 is not displayed on their website, so I guess it's an
> > old model and predates the compensation trick.
> >
> > As I said, it's the brand new scale that's got the problem. It's almost
> > certainly designed into the software because I can think of no way that
> > a fault could introduce behaviour like that, but I can think of why a
> > software designer would want to add that compensation, if he didn't
> > properly think through the consequences.
> >
> > --
> > Farry
>
> The kitchen scales use strain guages as the weight transducer. Although
> these are not linear in output (which is compensated), they do not exhibit
> the fault you describe. Its more likely to be a fault in the weighing
> platform suspension mechanism sticking (imagine a shaft going through a
hole
> and rubbing on the side). Probably a batch manufacturing problem. Check
the
> batch number of your model and take it back for exchange, making sure the
> new one is from a different batch/manufacture date.
>
> Dave
>
>