B8 ADS1115 current inputs

[jw1971]

Hello,

I am using Analog 1 and 2 for voltage inputs (A0_gnd and A1_gnd on the ADS1115) and these are working well.

I am trying to add a 4-20ma sensor to Analog 3 or 4.  It is a 12VDC sensor with 2 wires.  Red to +12VDC power, and black to current sense.  This 12VDC supply is the same supply that powers the B8.

The B8 on either Analog 3 or 4 doesn't show the current consumption - just sits at 1.49mA which is what it shows with nothing connected either.

If I use a DMM on 20mA range between the black wire and 12VDC GND I get 9.9mA which is reasonable.

Does the ADS1115 need some sort of ground bond to work in current mode?  What is the gnd return path for Analog 3 or 4?

[admin]

take a photo how you wire and problem with screen photo.

[jw1971]

take a photo how you wire and problem with screen photo.

It's really straightforward:

Supply 12V+ --> goes to Kincony B8 DC PWR 12V (+), and also to the pressure sensor RED supply wire.
Supply GND --> goes to Kincony B8 DC PWR 12V (-) input

Sensor BLACK wire (current drain) --> goes to Kincony Analog Pin 3 (and also tested pin 4)

ESPHome:

Code:

- platform: ads1115
  ads1115_id: ads1115_hub
  multiplexer: "A2_GND"
  unit_of_measurement: "mA"
  accuracy_decimals: 4
  gain: 6.144
  name: "${vessel_name} Level Pressure"
  id: "${vessel_id}_level_pressure"
  update_interval: 5s

I get no output.

If I remove from Analog 3 or 4 the black wire and attach it via digital meter on 20mA current range to Suppy GND ground I get 9.9mA which is what is expected.

It seems the ADS1115 is not using correct ground or an open between Analog 3/4 pin and the actual ADS1115 A2/A3 hubs.

Sensor:  

[jw1971]

take a photo how you wire and problem with screen photo.

Here is how it's hooked up.

   

[admin]

you can test with KCS v3 firmware, whether work well.

[jw1971]

Unfortunately this is in the service running rest of system and just adding this additional sensor. What does the ADS1115 use for Analog ground? Is that tied to the DC PWR 12V (-) input?

I know in some of the earlier Kincony boards there was a separate AGND for the ADS1115 side.

It is like this sensor doesn't have a ground path so why I am thinking it is something to do with the AGND and GND not being bonded.

[admin]

Is that tied to the DC PWR 12V (-) input? YES, all ground is same.