MSP430FR6043: Measure low 0.025 l/s and high gas flow 16 l/s

Eagerly waiting for a solution. We have bought close to 10k Microcontroller from Ti. This was CC2640 for another project. And it works perfectly. If you can help us with MSP430 issue listed above we have a requirement of annual 20k to 25k chips. Our requirement is to maintain the accuracy you are already giving for low flow and also cater for high flow. 

We are not too interested for High flow to be super accurate as that we can handle with some custom algo but it needs to be close to 98% accurate. Your low flow is 99.99% accurate which is why we are interested in this chip.

If this chip cant do what we want, we request you to help us with a chip in your portfolio that can help us to achieve what we are looking for. Our application is to build a Respiratory flow volume device.

Hi,

Where do you get the limitation with msp430fr6043 with measuring at 12000LPH. Is the limitation coming from the ADC capture window. Or the algorithm will return exceed the max sample shift limits? This one can be solved to use a larger setting of the USS_ALG_MAX_SAMPLE_SHIFT in the code.

And what is your application? Water meter or gas meter?

Best regards,

Cash Hao

Your data sheet mentions this limitation - Achieves ±1% accuracy up to 12000 liters/hour with a wide dynamic range of 200:1.

This is for GAS application.

Looking at your hardware, we feel its capable to do what we want but when we send more than 3 l/s air flow in a 30 mm tube with transducers arranged the way its shown in your demo video, the resolution drops. The data we get for under 3 l/s (12000 l/hr) is perfect but above that it struggles.

Is there a lock in the software? Is there a limitation on ADC or CPU and If yes, can you suggest how else can we achieve our goals.

Can you find out internally if this can chip has the capability to do what we intend to do?

I look forward to hearing from you. Many thanks

Any Updates?

Hi,

I could not tell what is the limitation in your case now. An assumption is that the gas flow changes a lot we the flow rate is larger than 3 l/s in your 30 mm tube. And it influences the quality of the receive signal and causes the software get a worse result. You can check the ADC capture data, compare the signal at lower flow rate and higher flow rate >3 l/s. Check if there is obvious change on it first. 

Best regards,

Cash Hao

Yes as mentioned in the above thread, the resolution is dropping and quality of data is not that good. How can we get better quaity data at higher flow rates. Our only constraints is the 30 mm tube diameter.