Belt Scale Integrator Replacement

S

Thread Starter

Shaun Bennett

Has anyone ever replaced a manufactured belt scale integrator with their own home grown PLC logic? I'm looking to replace our ancient Compuscale II integrators as they're way past the end of their life cycle. I can't imagine this is too difficult to do. We already do the PID control in the PLC, the only thing we're not doing is the calibration.

Does anyone have any calibration and integration routines they've already developed that could give me a few pointers?
 
W
There are at least 10,000 integration routines. This is a classic "how hard can it be" for software enabled engineers.

If you can somehow get a scaled pulse out of the scale, you don't have to integrate. That's the best solution.

Otherwise, hope the PLC has a tested integration subroutine.

Good luck. By the time you finish doing this, you will have spent four or five times the time necessary to pick up the phone and order a new factory tested, warrantied integrator.

And if you're using the integrator for a "pay me" function, be prepared to prove it works.

Ask me how I know....(rueful grin)

Walt Boyes
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R
Belt scales usually have 2 inputs Speed and weight, you would need a means of accurately measuring both.

I agree with Walt, it won't be cheap but if you have a number of non custody transfer scales it might be justifiable. It would certainly be an interesting project.

Assuming you are retaining the original weigh bridge and load cell you could purchase a good load cell transmitter. This would supply the exitation voltage and amplify the cell output or you could measure the output with a mV input card.

How would you measure the speed, with the existing transducer?

Roy
 
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