Gravity: Analog Current to Voltage Converter(for 4~20mA Application) แท้จาก DFRobot

• Support wide voltage of 3.3~5.5V
• Deploy 0.1% high precision sense resistor and ultra low noise rail-to-rail zero-drift op amp, high accuracy, and no need to calibration
• Wide measurement range up to 0~25mA, which is compatible with fault diagnosis, overrun detection applications

• Supply Voltage: 3.3~5.5V
• Detection Range: 0~25mA DC
• Measurement Accuracy: ±0.5% F.S. @ 16-bit ADC, ±2% F.S. @ 10-bit ADC
• Termination Resistance: 120Ω
• Connector Type: PH2.0-3P
• Product Size: 30mm * 22mm (1.18inch * 0.87inch)

• Product wiki
• More Documents

SHIPPING LIST

• Analog Current to Voltage Converter x1
• Digital Sensor Cable 3pin x1

Board Overview

Tutorial

This tutorial demo how to read the 4~20mA current signal with this module and Arduino UNO. The module input current is linear with the output voltage, as shown below:

Requirements

• Hardware
  • Arduino UNO R3 (or similar) x 1
  • Analog Current to Voltage Converter x 1
  • Sensor or Device(output 4~20mA current) x1
  • Gravity 3pin Sensor Cable (or several DuPont cables) x1

• Software
  • Arduino IDE (1.0.x or 1.8.x)

Connection Diagram

Sample Code

Before uploading the sample code, it is recommended that you use a voltmeter to confirm the actual reference voltage of the ADC on the main control board, and then modify VREF in the sample code, to improve the measurement accuracy.

/***********************************************************
DFRobot Gravity: Analog Current to Voltage Converter(For 4~20mA Application)
SKU:SEN0262

GNU Lesser General Public License.
See <http://www.gnu.org/licenses/> for details.
All above must be included in any redistribution
****************************************************/

#define CurrentSensorPin A2
#define VREF 5000 // ADC's reference voltage on your Arduino,typical value:5000mV

unsigned int voltage; //unit:mV
float current; //unit:mA

void setup()
{
Serial.begin(115200);
}

void loop()
{
voltage = analogRead(CurrentSensorPin)/1024.0*VREF;
Serial.print("voltage:");
Serial.print(voltage);
Serial.print("mV ");
current = voltage/120.0; //Sense Resistor:120ohm
Serial.print("current:");
Serial.print(current);
Serial.println("mA");
delay(1000);
}

Expected Results