10V Load Cell supplied in the field?
10V Load Cell supplied in the field?
(OP)
I have a load cell rated for 25000 lbs and such requires an excitation voltage of 10V. The DAQ board that came with it can only supply 5V and all this testing will be done in a remote location meaning I'll only have a truck as a power supply and any batteries I may need. How can I meet the 10V requirement so that I can accurately test. My circuits knowledge is quite rusty, if I invert the power from the truck to run a surge protector so that I can charge the laptop, can I run power to the load cell as well? Will I need to regulate the input into the cell from the surge protector? My other option is run straight from a separate battery but that would require a resistor in series, correct? The simpler the better.





RE: 10V Load Cell supplied in the field?
If that's the case, if you use 5V excitation, you'll get half the output than if you used 10V for excitation.
My impression is that many load cells are designed for nominal 10V excitation but will run at other voltages. Any excitatation fluctuation from nominal will be a direct proportional error though.
I suspect the load cell will run fine 5V. Why not call the rep/mfg and check?
The DAQ card scaling needs to take the excitation difference into account.
RE: 10V Load Cell supplied in the field?
RE: 10V Load Cell supplied in the field?
RE: 10V Load Cell supplied in the field?
RE: 10V Load Cell supplied in the field?
The point being that the load cell output is "mV per excitation volt". If the excitation jitters, the output jitters. Stable source voltage is assumed for this type of measurement.
I have no idea how well USB voltage is regulated or filtered. Maybe others do.
RE: 10V Load Cell supplied in the field?
RE: 10V Load Cell supplied in the field?
RE: 10V Load Cell supplied in the field?
TTFN
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