Issues with ADS1115 16-Bit 2-Channel

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.

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

The ideal product for your application will be this one


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

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?

yes it works with RPI