Issues with I2C Current Shield, 1-Channel 4-20 mA current loop receiver, and an Arduino setup


I currently have an I2C Shield for Arduino Uno:

a 1-channel 4-20 mA Current Loop Receiver 16-Bit ADS1115 I2C Mini Module:

an Arduino Uno

and a flowmeter:

I purchased this flowmeter from EBay and want to test that it works. It outputs 4-20 mA, hence why I’ve purchased the shield and current loop receiver. I have connected the flowmeter (which isn’t shown in the image, which is powered by a power supply also not shown in the image) to the 1-channel current loop receiver and connected this to the I2C shield. The green wire is ground and the purple wire has the signal, which are both in their respective places in the current loop receiver.

I used the code mentioned here:
Reading 4-20mA Current Loop Sensors using Arduino - and generally followed it for the wiring/connections.

However, both when I have nothing flowing through the flowmeter and when I have liquid passing through, the output I get is 0 mA. I’m aware that when I have nothing passing through, the current should be at 4 mA. I’m wondering if the issue I’m having is related to my wiring of the system, the components I’m using, or the actual flowmeter itself.

Let me know if any part of this explanation needs clarification, better images are needed, etc. Thanks for your help.

when nothing is flowing the mA value should be 4mA. 0 indicated that’s there is wiring issue.
did you try to swap the wires ?

When I swapped the green and purple wires, the output from the arduino was 20.5 mA even without a flow and the current receiver got very very hot so I had switched them back because I figured that shouldn’t be happening.

Yes it should not be getting hot.
the wiring diagram shows that the sensor is 3 wire. do you know if the model you have is 2 wire or 3 wire ?

Model as in the model of the flowmeter that I have?

Yes the part number of it

Serial Number: W21487002
Type 3750C-MAT

can you share a picture of the flow meter wiring
Also did you use a multimeter to make sure the sensor is indeed outputting a mA signal ( around 4mA)

I tried to measure it with a multimeter but it didn’t have mA option only A, I wasn’t getting any reading and assumed it was because mA was too small to measure with it.

Coming from the flowmeter I have three wires, the flowmeters schematic in the manual has black being positive power supply, white being negative power supply, and the blue wire I’m using is the signal. I split the black and white wires and have them connected to the power supply each with a bigger wire. I also split ground (the bare/uncovered wire) and did the same thing. The ground and in wires that are plugged into the current receiver come from the splitting of ground and splitting the blue wire that is directly connected to the flowmeter (I did this just to increase length).

I think the first step will be to make sure the sensor is working and outputting the 4mA.