You can put together the 4 signals of the load cells, using a Juction
Box, this is for can ajust each load cell

Francisco Armenta

Brent Brown wrote:

> Hi,
>
> I'm working on a new project that will be using 4 load cells to
> measure the weight of a piece of machinery during operation.
>
> I've seen weighing platforms that use a load cell on each mounting
> foot - presumably they just average the four readings to get the
> total weight eg. (A+B+C+D)/4 ?
>
> Can I minimise the electronics by putting the outputs of the four
> strain gauge bridges in parallel (maybe with some series resistors)
> and then just use one bridge amplifier and one ADC input on my
> micro? (Rather than 4 x bridge amps, 4 x ADC's)
>
> Would this affect linearity much?  My dynamic range of weight is
> very small, I'm looking to measure 0-20kg change (product) on top
> of a constant 500kg or so (the machinery itself), and 0.1 or 0.2kg
> resolution would be fine enough.
>
> Also, what are your favourite bridge amplifier's for a job like this?
>
> Hope these are simple questions to answer for people with
> experience here, and interesting for the rest of us!
>
> Thanks in advance, Brent.
>
> Brent Brown
> Electronic Design Solutions
> 16 English Street
> Hamilton, New Zealand
> Ph/fax: +64 7 849 0069
> Mobile: 025 334 069
> eMail:  brent.brown@clear.net.nz