How to Recreate a mV signal?

Question

I'm working on a project with an 2 Arduino's to transmit a load-cell's signal. I'm very new but fell I have an understanding enough for this project except for the last part.

I plan on using an op amp to boost the signal into the first Arduino but need to get the second to bring the signal back to it's original mV form, so really the question I have is what component to do this with?

The load-cells specs:

Operating range: 0 to 50,000 lbs

Input Voltage: 5 VDC

Zero Offset: 0 mV at zero load

Output Voltage: 2 mV/V ±1% at rated load

The loadcells output is 2 mVDC of excitation at full load of 50,000 lbs, my signal voltage will be somewhere between 0 and 10 mVDC.

So this doesn't fully apply to Arduino but this is the only place I could think to post my question.

Thanks for any and all help

Matt

dougw · Accepted Answer

An arduino can provide an analog output 2 ways: by generating a PWM output (using the analogWrite() function) which is then filtered externally to create an analog signal. by digital-to-analog converter (on an arduino Due) also using analogWrite() To reduce the voltage all you need is a pair of resistors connected as a voltage divider or a potentiometer. The resulting low level signal could be buffered with a voltage follower op-amp to simulate the low impedance of the original load cell.

michaelkellett · Answer

Amplifiers and excitation for load cells is a complicated topic. You haven' specified enough to comment on the kind of approach you will need.

The additional information required is:

maximum error permitted in measurement

measurement intervals e in 50000 lbs (often 1500,3000 or 6000)

response time

working temperature range

are there any legal or safety implications

MK