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Using the 4-20 Receiver

Newbie question:

Well, I got the 4-20 receiver for 3 sensors. I am using BeagBone and got also its I2C cape.  So BeagleBone is connected through the I2C to the 4-20 receiver, that is connected to 3 4-20 currnet look sensors.

How do I operate it? How do i get the current measurments from my 3 sensors?

Where can I find programming guide or user manuel?



this board has an ADS1115 on the board. you can use this python lib to read the sensor values.


once you get the adc value you can check out this tutorial to convert these values into real world values.





Thanks Bhaskar,

What i cann ot find is how to configure the ADC correctly for this board?  For example, the board has 3 4-20 inputs. How do i select which one to measure?  Missing all board-related configuration. Thanks




you will need to use the ADC as single ended. in the python code you can find all configurtion


To read 4-20mA you can use the ADS1115 in default mode. You can change the settings like bit resolution, sample rate based on your accuracy and speed requirement.




Can I assume that for the first 4-20 input I need to cofigure 0x40 # Single-ended P = AIN0, N = GND,
for second input, 0x50 # Single-ended P = AIN1, N = GND

and for the third input 0x60 # Single-ended P = AIN2, N = GND

The phyton example just defines the command info but do not suggest what should be configured for this specifc board.



Is that correct?




Yes, thats correct.



Any other configuration needed to the ADS1115 that are specific for this board?


For the life of me I cannot get this receiver to give me readings that make sense. If I just load the github code into my photon, and do not connect a transmitter, I get -4138 as a reading. If I connect a 4-20ma (0-100psi) pressure sensor to it, I get 26112. This really doesn't make sense because that means that every mA = 7562 bits, so there wouldn't be enough range to get us to 20mA?? Any help is appreciated.



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