Issues with ADS1115 16-Bit 2-Channel

[johanschwind]

Hi all,

I’m looking to connect a Picomag flowmeter to the ADS1115. I’ve confirmed with a battery powered 4-20 mA simulator that the reference code from NCD works properly on my Arduino.

The flowmeter has a voltage input which is 18-30 V, a GND, and a 4-20 mA output wire. When I measure the current from the output to GND on the sensor, it works properly and shows a reading between 4 and 20 mA based on flow.

The issue is that when the flowmeter is connected to the ADS1115, the raw ADC readings drop to around 300 and are unresponsive to the flowrate. I assume this is because the sensor uses a separate power supply, rather than being powered from the ADS1115. Is there a way to fix this?

I’ve attached a quick diagram drawing to illustrate.

[Bhaskar]

Yes both power supply are fighting each other.
here is how it can be done

Type 4 Current Loop with PR33-7

Hi, I have a laser range senor that has Power, GND and a 4-20 mA output and I bought the 2-Channel 4-20 mA Current Loop Receiver 16-Bit ADS1115 I2C Mini Module (SKU PR33-8). I did as above where I connect 4-20 mA output from the sensor to IN1 and GND to V COM. The laser sensor is powered by 24 VDC. I have a multi-meter in series and current reading is fine but i get no data when reading the i2c bus. I have used the example code from https://github.com/ncdcommunity/Raspberry_Pi_ADS1115_16Bit_…

The ideal product for your application will be this one

4-Channel I2C 4-20mA Current Receiver with I2C Interface - NCD Store

thanks

[johanschwind]

Thanks for your quick response! I’ll try the component you recommended!

[osufarmer2010]

Bhaskar- Just wanted to confirm before ordering the product you recommended above. Will this also work with raspberry pi and is there a python library available for it?

[Bhaskar]

yes it works with RPI

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