I have a Druck pressure sensor, model PDCR-5011-TA-A3-CA-H0-PF-15PSIA. The sensor output is 0–100 mV, and I would like to interface it with an Arduino to measure pressure.
How to go about it. Please provide your suggestions with regards to wiring, power supply, and required suitable components.
Welcome,
Please post a link to the datasheet.
Have you read the datasheet to know how the device works?
I am not familiar with this exact type, so more information is welcome.
Please find the link. [Druck pressure sensor 0 to 15 psi A]
How much resolution do you need?
Around 0.2 % of FS ( 15 psi). That is around 0.03 psi.
So you have a 100mV output and you need to read with a precision of 0.2mV. That's not too bad: the standard 10-bit ADC on an arduino can handle that. What you will run into problem with is the voltage level. It would need to be amplified by about 20x to get the output you want.
However, you might find that instead of amplifying, an external high-resolution ADC is easier to work with. The ADS1115 is a possibility and there are many Arduino breakout boards and libraries that support it.
Next is the problem of supplying the sensor with a precision excitation voltage. Unless it has an internal reference, the sensor's output voltage will be a function of the input, so if that input varies, so will the output. One way around this is to read both the input and output and compensate the output for any variations in the reference voltage.
That should hopefully get you started.
This will give you more resolution than you need.
Which Arduino you had in mind?
I am considering Arduino Nano. Overall I am planning to have like this, 1) Arduino nano board with USB , 2) Amplification module such as ADS1115 or similar , 3) Display for pressure readout. Is this correct approach ?
Is this correct approach ?
Make your life easier and use my suggesion. Its made for your specific application. No need to try to roll your own device.
See post #7
The Druck PDCR 5011 has a mV linearized output and the power supply is listed as a minimum of 7 V to power the internal circuitry that provides that linearized output. At the 10 V nominal power supply/excitation voltage, in order to preserve the ratiometric characteristic of the output, finding an ADC to accommodate that is problematic.
Do you already have the transducer or can you get the mV passive instead? With that you could use a lower bridge excitation voltage and you would have more choices for conditioning.
Added:
If you already have the transducer the most practical solution may be to power it with a precision reference as @cedarlakeinstruments has suggested (maybe LT1021-10 or AD587) and use an available ADC module like the ADS1115.
Poor choice, wrong type of A/D. You need a ratiometric A/D for bare Wheatstone bridges.
Go with jim-p's recommendation and use an Arduino board with STEMMA/Qwiic connector, or use a HX711.
Op should have bought a sensor with (4-20mA) current output.
They are easy to interface with an ADS1115.
That makes this sensor harder to interface with a microprocessor.
The old "10volt" excitation way is with chips like the INA125, followed by an ADS1115.
Leo..
Exactly.
@chandra_1 if you don't already have tue sensor on hand, I have had good luck with Novasensor I2C pressure sensors. They are precalibrated and provide a 14-bit digital output making them very easy to use. IIRC, the ones I'm using are accurate to about 1%.
If OP is stuck with the transducer they posted and are determined to use the ADS1115, reasonable accuracy can be had by using a very accurate reference chip for excitation as only 3 mA are needed. They won't get the 0.04% accuracy they paid for though.
Your suggestion to measure the excitation voltage was the solution I used along with some ultra precise Vishay resistors in the 70s. Back when a 12 bit Burr-Brown a/d cost $200.
I2C or 4-20ma is more a practical choice, dictated by the distance between sensor and electronics. I2C limit is measured in cm, 4-20mA is measured in metres.
If you're going to use a voltage reference chip to power the sensor, then use the INA125.
It has both excitation voltage reference and instrumentation preamp.
Note that an ADS1115 + 10volt reference alone won't work.
The two sensor outputs would be outside the ADS's common mode range.
The intermediate step of the INA125 would solve that.
Leo..
A $3.30 100kPa (15psi) sensor from ebay with integrated HX710 would do the same, and easier, than that expensive sensor with the wrong choice of electronics.
It seems that OP has bought a Lamborhini, not realising the village has a dirt road an only diesel fuel at the gas station.
The thing is that we already have the pressure sensor model PDCR-5011-TA-A3-CA-H0-PF-15PSIA, along with a DPI 280 display unit, but the display is not functioning properly. That is why I started exploring alternative methods to read the pressure using an Arduino. The sensor provides an output signal in the range of 0 to 100 mV.
