Fluctuating ADC Reading for 4-20mA Pressure transducer input

[BHARGAV SHANKHALPARA]

Hello...

I am working on one project of water pressure measurement, in which i used pressure transducer which gives me output between 4-20mA Current form.

I am using one 250 ohm resistance to convert current into voltage, and than i give this voltage to ADC of arduino UNO channel 0 (A0).

ADC reading is continuously fluctuating up to 10 decimal numbers.

I have also check by connecting multi-meter and measure sensor current reading, for particular pressure. but current reading is stable (even not fluctuate 1 or 2 points.)

also i have checked voltage value after 250 Ohms +Ve and ground. converted voltage is also showing very stable.

but why ADC reading is fluctuating..?

i am using arduino uno, i doesn't have any changes in AREF, AVCC etc...

please suggest effective solution,

Thank in advance.

 

[WHONOES]

Is the reference stable?

 

[BHARGAV SHANKHALPARA]

Is the reference stable?

Yes, i have doest change in AREF pin, it is same as provided default.

Is the reference stable?

 

[Alec_t]

If the UNO has a 10-bit ADC, the fluctuation is an error of ~1%. Noise on the ground rail could account for that.
How close is the UNO ground connection to the 250 Ohm ground connection? Are you using twisted pair or screened cable for the inter-wiring?

 

[BHARGAV SHANKHALPARA]

Hello Alec_t..

I actually connected 250 Ohm resistor directly on arduino board between pin A0 and Ground.

my sensor wire is around 300 feet long, which is 2 core insulated wire, as sensor is giving 4-20mA current output, which is highly immune to noise.

conversation of current to voltage is take place on arduino board.

 

[Bluejets]

There is a single line of additional code that will reduce analog input fluctuations in Arduino.

 

[BHARGAV SHANKHALPARA]

There is a single line of additional code that will reduce analog input fluctuations in Arduino.

Please suggest me that single line code.