2-Channel 4-20 mA Current Loop Receiver

Hardware
1

@Bhaskar I have this unit on a Feather ESP32 with headers wired to the I2C channels. On the Feather ESP32 the SDA/SCL are different than other boards.

When using feather’s I2C pins, use this code in ADS1115.cpp:
#define SDA_PIN 23 //default is 21
#define SCL_PIN 22 //default is 22
Wire.begin(SDA_PIN, SCL_PIN);

The problem I am having is that my Pressure Transducer works on my PLC’s, ( I have tested with 2 separate ones) But it doesn’t work with this board. I have read of others having to remove things off the board?
–Type 4 Current Loop with PR33-7

I spent over 70 per board, and I don’t like the idea of having to modify them, lose the warranty just to get them to work.

Any ideas of what I can do, either way?
Thanks,
Dan

2

Hi Dan
Please can you share the datasheet or the part number of the pressure sensor you are planning to use with this board?

is it a 2 wire sensor?

Thanks

3

Hi,

Thanks for responding.

It is SKU: PR33-8

It is a 2 wire sensor, external power 8-32v. I am powering with a 12v power supply.

Thanks,
Dan

4

Hi Dan,
If its a 2 wire sensor then you can power it using the PR33-8.

If you are powering using external power supply then it might be a 3 or 4 wire sensor.

for that you will need a different board.
https://store.ncd.io/product/4-channel-i2c-4-20ma-current-receiver-with-i2c-interface/

Thanks

5

Hi,

So the part I bought is intended to provide power to the sensor? Our sensor can be powered by a rand 8-32vdc. So the 16v provided should work and I need to disconnect my power supply to the sensor.

Your other board allows the sensor to be powered externally?

Thanks,
Dan

6

In general there are two kinds of 4-20mA sensors. one which can be powered and read 4-20mA signal using same wire. other one are which have separate connections for power and 4-20mA signal.
without the sensor datasheet i cant say how it works but you can give it a try.

Yes, the PR33-15 works with the sensors which are powered externally.

Thanks

7

Thanks,

I appreciate the clarification of the 2 products. In the end I didn’t read the description well enough to see you had a product for each type.

Dan