The way I understand this is I should be able to supply 12vdc to the black and red, and then read the reference voltage across green and white, but his hasn't been the case.
The part I think I am missing is either a connected ground or a load / burden resistor or both.
I thought my understanding of isolated was the supply voltage grounds are not connected and the sensor diaphragm uses a silicon oil to pass the pressure hydraulicly. (Looks like this model doesn't but you get the idea)
I don't want to cook my multi hundred dollar sensor so I figured I should ask first, burn later.
I see green is listed as millivolt only, and I have the 1-5v option, so I assume I only need to connect my white cable to an analogue in but the (signal negative) part confused me.
I will be using a 12v PSU for the sensor (excite range is 10-28vdc) and a voltage converter to supply 5v for the ESP32.
Is it as easy as just connect the grounds of the PSU/sensor and the arduino or is a smoothing capacitor and or 10k Ohm resistor placed somewhere also needed?
As stated, this is the series 40, 3000 PSI, 1-5vdc not sure why you need to know cable and NPT size but here you go, I appreciate the help either way :
if you look at this table, the sensor would have a model of something like: 40-A-03000-p-3-T-0-C0S
I just figured I would save the readers some time in deciphering it.
To use that sensor with an original issue ESP32 (which has a very poorly functioning, highly nonlinear ADC and is not at all recommended for serious measurement purposes), a resistive voltage divider is required.
You can use 5V to power the ESP32-S3, if the MCU module includes a 5V to 3.3V regulator, which is likely the case. A resistive voltage divider is required between the sensor and the analog input.
Thank you for that tip, I had used an arduino that accepted 5v in to an analogue port in the past and just assumed that this one would too. I just confirmed in the spec sheet a max of 3.6V. That saved me a cooked board!
What you have is a pretty common sensor. Here is where I see a problem. Your sensor is 0 to 3,000 PSI and that corelates to a 1 to 5 volt output. That gives you a 4.0 volt span. So if we divide the 4.0 volt span by 3,000 PSI we get 1.333 mV per PSI. Pretty small number there. Trying to resolve it is a bit of a challenge. There are some pretty useful ways around this. Personally I would run with an ESP8266 or ESP32 and add an ***ADS1115 I2C IIC Analog-to-Digital ADC PGA Converter with Programmable Gain Amplifier High Precision ADC Converter Development Board for Arduino. There are plenty of examples and code samples online and Google is your friend. This gives you a 15 bit ADC capable of I2C communication. There are newer higher resolution ADS but 15 bit with PG (Programmable Gain) should be adequate.
This is how I would go about it. There are other ways to get it done. The ADS1256 gets you a 24 bit A/D. I have used the ADS1115 with an ESP8266. Something to note is when they say a 16 or 24 bit A/D typically a single bit is used for sign so in reality the A/D is really 15 or 23 bit. Anyway, it's something to consider.
I just got everything working.
Just the one wire (white) connected to an analog in on a Arduino Uno clone did the trick aside from the 12v power in to the sensor and the combined grounds of the sensor and the 5v voltage adaptor for the arduino.
The spec sheet showing the white wire as a negative voltage out was confusing for me, and so I just needed a confidence boost from the community
No additional resistor or capacitor needed thus far.
I am looking right now at a nice stable value of 0.9677 Volts.
I am going to see if this resolution will suffice for my needs.
Thank you @Ron_Blain for the gain amplifier idea. it has been a long time since I played with one of those in EE in University and forgot all about how it could be used to increase bit depth.
Impossible.
You're mistaken.
Any current must be closed.
If you have only one wire working, it means the sensor's power supply and its sensing circuit share the same ground with the Arduino.
Otherwise, your result has nothing to do with reality.
Glad you have it working. Keep in mind an Arduino Uno has a 10 bit ADC and when using its 5.0 volt reference for A/D we get 1023 bits so we actually have 5.0 / 1023 = 4.88 mV. The best you will resolve is your 4 / 3000 = 1.333 mV per PSI so about 3.7 PSI per step change. Now if that is adequate you will be fine.
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