I am a little confused about wiring output+/output-. I just wanna read the sensors voltage (0-40mV span).
my AREF is about 49,0mV. Serial.print shows the max value 48,5mV
I've connected output+ to A0, and output- to ground. So It's wrong but I couldn't figure out the correct way doing that.
the code is pretty simple:
int analoginput = 0; // our analog pin
int analogamount = 0; // stores incoming value
float percentage = 0; // used to store our percentage value
float voltage =0; // used to store voltage value
void setup()
{
Serial.begin(9600);
analogReference(EXTERNAL); // use AREF for reference voltage
}
void loop()
{
delay(200);
analogamount=analogRead(analoginput);
percentage=(analogamount/1024)*100;
voltage=analogamount*0.0478515625; // in millivolts 0,04785 = (49mV /1024)
Serial.print("voltage on analog input (mV): ");
Serial.println(voltage,2);
}
I don't think that you can set the Aref to 0.049V and have it work. What output do you get raw form the analog input with 0.049V applied? What board are you using? Model of transducer?
edit: I have used these sensors and they are not real user friendly. The output needs to be amplified and level shifted to be read by an analog input. The output is ratio-metric with supply voltage so the supply must be rock solid. And no temperature compensation. I would look for the sensors that have a 0 to 5V output. They have built in supply regulation and temp compensation.
Normally, the GROUND to Arduino GND, the +SUPPLY to 5V and the +OUTPUT and -OUTPUT (those are the bridge outputs) to an OpAmp and the output of the OpAmp to an analog input of the Arduino.
But only if the sensor can be used with 5V.
Which sensor is it ?
When used with 5V, the outputs will be between 2 and 3 Volt. So they can be connected to analog inputs. It will be very inaccurate, but this page describes that tric: Arduino Playground - SPX3058D
I,m currently building a project to test SCUBA regulators. This sensor your using looks like a Honeywell differential pressure sensor, but I chose to use the I2C model VERY easy to hook up (works great!), my pressure sensor on the other hand (250psi, has an o/p 8.5mV/psi) is similar to yours (bridge o/p). This requires an instrumentation amplifier (I'm using an OP177), this will raise the o/p to a value that the analogue i/p can read with no problem.
groundfungus:
I don't think that you can set the Aref to 0.049V and have it work. What output do you get raw form the analog input with 0.049V applied? What board are you using? Model of transducer?
edit: I have used these sensors and they are not real user friendly. The output needs to be amplified and level shifted to be read by an analog input. The output is ratio-metric with supply voltage so the supply must be rock solid. And no temperature compensation. I would look for the sensors that have a 0 to 5V output. They have built in supply regulation and temp compensation.
Hi,
I have attached a multimeter for measuring mV, converting it in Excel and complete the job, but I was looking a smarter way doing that.
Aswering your question, the signal output is 0.00485V. Arduinos board UNO R3, and MPX2050DP transducer (10V - 16V). I work with that kind of transducer, for measuring differencial pressures between inlet and outlet of a heat exchanger.
AREF is provided by 3.3V ARduino source pin and 3 series resistors for bringing down to 0.0049V
Erdin:
Normally, the GROUND to Arduino GND, the +SUPPLY to 5V and the +OUTPUT and -OUTPUT (those are the bridge outputs) to an OpAmp and the output of the OpAmp to an analog input of the Arduino.
But only if the sensor can be used with 5V.
Which sensor is it ?
When used with 5V, the outputs will be between 2 and 3 Volt. So they can be connected to analog inputs. It will be very inaccurate, but this page describes that tric: Arduino Playground - HomePage
I have this op-amp on my hands, but it says I can't apply do DC transducers
the sensor is MPX2050DP (10V - 16V supply) and (0 - 40mV outuput range)
TerryScubaT:
Hi,
I,m currently building a project to test SCUBA regulators. This sensor your using looks like a Honeywell differential pressure sensor, but I chose to use the I2C model VERY easy to hook up (works great!), my pressure sensor on the other hand (250psi, has an o/p 8.5mV/psi) is similar to yours (bridge o/p). This requires an instrumentation amplifier (I'm using an OP177), this will raise the o/p to a value that the analogue i/p can read with no problem.
Hope this is helpfull.
Terry
Man, where did you buy it? I got attracted by I2C bus communication characteristics, it's very friendly
