Questions tagged [4-20ma]

In industrial environments 4-20mA is a commonly used range of values for a current loop where 4mA represents the lowest value and 20mA indicates the maximum. Some advantages compared to sending a voltage is that the resistance of the cable doesn't affect accuracy and devices may be powered from the same pair of wires.

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4-20 mA Sensor to Raspberry Pi: Inconsistent readings

I have a 4-20 mA sensor that I want to read it with a Raspberry Pi. I use a DFRobot Current to Voltage converter board connected to an ADC (ADS 1115) that is connected to a Pi. So that way I can read ...
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4-20ma current loop and ESP32 [closed]

Following a previous question I'm thinking of using the following design for a 4-20ma 24VDC preasure sensor with an ESP32 ADC pin Will it actually work? Should I add aditional protection like two ...
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4-20 mA current loop with a 3.3 V microcontroller

I have an analog pressure sensor that I am trying to read. The sensor is powered by 24 V and outputs a 4-20 mA signal. I want to connect it to an ADC pin of a 3.3 V micro. There are two designs I'm ...
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Circuit for 4-20mA to I2C conversion

Hello I have a circuit that takes a 4-20mA reading from a pressure transmitter and converts it to analog 0-5V then to I2C. But it doesn't seem to be reading I just see about 0.5V on the serial ...
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Multiple receivers on a 4-20mA loop with one of them with common ground

I'm trying to design a PCB to read some 4-20mA sensors in an already existing setup. The existing setup uses a NI 9207 adquisition board, which has an input impedance of 85 ohm per current channel, ...
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Resistors at ADC input of 4-20mA receiver

I'm looking into building a 4-20mA receiver and found a reference schematic. In the description, they state that it uses a resistance value of 150 Ohms to produce a 3 V when the sensor's output is ...
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Interfacing Burkert 4-20mA flow meter to controller

I am figuring out how we can interface the flow meter to our controller before moving onto the software part. I have never worked with a 4-20mA interface hence just looking for some advice. Below ...
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Power considerations in active analog outputs

I need to build 2 active 4-20mA outputs from a 24V supply voltage with unknown load conditions. One basic solution could be like the schematic below. VIn is converted to a current through R1, ...
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Current Source - using Op-Amp and MOSFET

I would like to implement the current source circuit above to output a 4-20mA. Vin coming in from non-inverting input on IC1 is 0-5V. I am also adding 1nF capacitor and 10k resistor as shown to ...
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4-20 mA analogue signal conversion to flow rate

I have the following control setup: For that, I have data recorded for every I/O block, and I am asked to determine the function used by the AIN block to convert from an analogue 4-20 mA signal to a ...
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4-20 mA sensor output to STM32 ADC input

I have a industrial sensor with 4-20mA output and I want to read that output from Stm32 ADC pin but I need suggestions to do that work in a nice way. Can you guys suggest me the best way to do it? It ...
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How to make 4-20mA Sink Generator to Simulate with PLC or other 4-20mA Instruments? [closed]

I want to test Pressure Transmitters without actually pressure available in LAB. So I want to make 4-20ma Simulator. I changed my Title to 4-20mA Sink Generator. As I am referring to 2 Wire ...
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4-20mA sensor to a microcontroller

I need to connect a sensor with a 4-20 mA loop to a microcontroller. The MCU operates at 3.3V and the following image is from the sensor's datasheet. I'm planning on converting the 4-20mA to a 0.6-3V ...
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How can I create feedback measurement with an operational amplifier? 0-20mA measurement

I want to build something like this. This circuit controls 0-20mA but the circuit have one big problem. If the circuit load e.g 100 Ohm changes to e.g 200 Ohm, then less current is going to flow. To ...
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4-20mA to voltage breakout: part identification

I am trying to recreate the SEN0262 current to voltage circuit and embed it into my own board. As you can see, the schematics looks pretty good, but I'm unable to identify the D1, D2, and D3 diodes. ...
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pt100 RTD transmitters not working - two in a row - am I doing something wrong?

I just tried to use two different ones of these RTD transmitters with a pt100 probe (3 wire) with no success. I am connecting the transmitter directly to a 4-20mA input on a PLC, as shown in the ...
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Where to properly terminate 4-20mA cable shield in ungrounded low voltage DC system?

Preface: I read both: ungrounded chassis shielding and: RS485: Where to connect the cable shield in a battery-powered system? A sensor system I'm working on is getting installed in a 20x20' cement ...
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Can 4-20mA transmitters send through a 1kOhm resistor?

I have a 4-20mA sensor at work and I wonder if it's possible if a 4-20mA transmitters send through a 1kOhm resistor? I guy I talked to said that 4-20mA normaly can't send through 1kOhm because it's to ...
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Frequency Key Shift technique to superpose the digital communication on top of 4–20 mA signals

I start working with HART devices and I really try to understand how digital data is transferred trough 4-20ma current loop. I start read this article: https://instrumentationtools.com/hart-...
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circuit for converting in 0-5v to 4-20mA current source

basically is want to make a circuit that takes 0-5v input and converts it in and corresponding output current of 4-20mA using opamp , i have seen reference circuit from this pdf https://www.analog.com/...
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LTSPICE time step to small for (0-5V) to (4-20mA) converter

i am trying to simulate a (0-5v) to (4-20mA) coverter circuit .when i am trying to the transient analysis of the circuit in the Ltspice i getting a time step error i have kept stop time as 100 for ...
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VIH of digital selection inputs for analog Mux when supplied with 4096mV - CD4051 IC

I will use CD4051BM96 part number, DATASHEET On page 7 is shown specs of VIH. It shows VIH of 3.5V for 5V supply (this 70% of VDD), VIH of 7V for 10V supply (70%) and VIH of 11V for 15V supply (73.3% ...
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Automotive Sensor Output

Why does the automotive industry sticks with 5V sensor outputs instead of something like 4-20 mA? Wouldn't it be a solution less prone noise? What are the advantages in using a 5V output instead of a ...
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Designing signal conditioner to convert current source to voltage output

I've seen a lot of signal conditioners online for converting a 4-20 mA current loop signal to a 0-10 voltage output. However, they seem extremely expensive for the task they are achieving. Are the ...
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Measuring 4-20mA with differential ADC

I have a question. Is it a good way to measuring 4-20mA with differential ADC? Assume that we have a ADC with 2 single ended inputs or 1 differential input. Input A+ is the first input and input A- is ...
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ADC Input Protection with 4-20mA

If you've got a 4-20mA transducer, powered by 14V, and you want to measure it, your analog front end might look something like this: simulate this circuit – Schematic created using CircuitLab .....
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Battery powered 4-20mA sensing application

I have a base system that runs on 3-AA batteries which it regulates to a system voltage of 3.3V. I want to interface that system to measure a 4-20mA sensor. For the sake of argument, lets say that ...
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Converting a 4-20mA 24V signal to 0-5V?

How do I convert a 4-20mA 24V signal to a 0-5V signal, suitable for A-D conversion with a 5V microprocessor? Can this be done while isolating the 24V from the 5V output?
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4-20 mA PID controller PCB Layout

I have designed a 4-20 mA PID controller using atmega 328p, MCP4922(DAC), XTR115UA(4-20 mA current loop transmitter) I used the circuits proposed in datasheets and the PCB and schematic files are ...
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4-20mA output from Arduino Nano

To convert 1-5V to 0-20mA: When I use 3.3V ouput from Arduino Nano Power Pin--> Iout = 13mA (which is ok). Similarly, with 3.3V Battery -> Iout = 13mA (which is ok). But, when I use 3.3V ouput ...
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4-20 mA output from Arduino for VFD

I'm a beginner with electronics, so everything has to be explained in simple terms to me. I have an Arduino with a program which provides a value via the Analog output, so that is anything from 0-5 V....
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Is this an elegant approach for a simple, debounced tank level controller?

I am interfacing some industrial (24v) process control equipment to some new projects in the embedded realm of electronics (3.3/5V small signal) and am coming up with some simple solutions for ...
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4-20 mA Loop voltage Implementation using XTR115

I want to Implement 4-20mA current loop using this circuit that is proposed in the IC datasheet. I used 7805 regulator to Implement Vloop and this is my Schematics. will this work? Edit: the load is ...
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Correct way to measure a 4-20mA sensor?

I have an 0-10V analog input channel that I would also like to measure 4-20mA sensors. I have added a 500 ohm shunt resistor I can jumper in when I am using the 4-20mA instead of the 0-10. Can this be ...
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4-20 mA to 0-3.3V converter

I have a 4-20mA signal and want to feed it to my uC. I found this circuit but dont know how it works. can any one explain this for me? or suggest a better solution
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4-20mA to switching output

I have a 4-20mA output. I need to turn an LED on when let's say 20mA is reached. I can obviously do this easily with a plc or an Arduino, but I need to do it as cheaply as possible. Is there a simpler ...
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ATMEGA 2560 => MCP4725 => FC-33 => Electronic Pressure Regulator

I am purchasing a regulator that accepts a 4-20mA control. I am hoping to interface this to an ATMEGA2560 microcontroller. I am looking at using a MCP4725 DAC driven by the I2C bus of the ...
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Best practice in transmitting sensor analog signal over longer distances (approx. 100') -- in cost sensitive products for microcontrollers

I'm looking for best practices for transmitting an analog sensor signal over long distances to a microcontroller such as the Arduino running at 3.3v or 5v. Keeping costs low is imperative. SPI and ...
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3 votes
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Controlling a 0-20mA transmitter from an isolated PWM signal

I'm trying to generate a 0-20mA signal for controlling an industrial actuator (the position of a 3-way valve) from a Teensy 3.2 system. Preferably, the mA-output should be galvanically isolated from ...
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Voltage controlled current source using op-amps

I have a sensor which gives a voltage output between 0V and 5V. I need to transform this sensor output to a current suited for a 4..20mA current loop. The thing is, the current loop doesn't have a ...
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4-20mA PLC analog output ground referencing for other devices

I'm currently using a PLC to control an induction heating coil. I'm using a chinese induction driver that allows 4-20mA PID input. This device runs off standard australian 230v AC 50hz. I've ...
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DAC7760 voltage and current output

I use the following function to send data from STM32f1 to a DAC7760: ...
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XTR111 4-20mA to 0-10V issue

I have below circuit which produce 4-20mA and by adding resistor (before the TVS) I can get 50ohm => 0-1V 250ohm => 0-5V but unable to get 0-10V since when I add 500ohm resistor, the voltage max out ...
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How/can I plug a 3 wire 4-20mA current sink probe into a 2 wire 4-20mA loop powered controller?

I have a 3 wire 4-20mA output probe simulated here, where during normal operation the 20v and 250 ohm resistor are variable chosen by the user. One of my users has a 2 wire 4-20mA meter, and I am ...
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Is a current varying output or voltage varying output for a 4-20 mA sensor more reliable for a rocket?

For the internal plumbing system of a rocket which is expected to reach 100 km above the ground, industrial pressure sensors with a 4-20 mA current output and a 0-10 VDC output are available. What ...
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Common ground b/w power supplies and analog pin for microcontroller

Referring to the schematic below, is it best practice to have the 5 V supply on the right powering the MC (arduino-esque microcontroller) share a common ground with the 24 V supply ? The 24 V supply ...
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What happens when a 4-20mA sensor is connected in reverse to receiver?

simulate this circuit – Schematic created using CircuitLab I need to build a 4-20ma to 1-5v converter circuit. I have a working model with a 24v supply and a 250 ohm resistor. Now I need to ...
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measure 4-20 mA and also power from loop powered

we know to give a command to an actuator in instrumentation we use 4-20 mA loop power. for reading this 4-20 mA I used the circuit below.so the problem is if my circuit only consumes 3mA, how should ...
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Conversion 0-20mA to 0-5V [closed]

Have you ever used this device? https://fluxworkshop.com/products/biaa100070-lm358-a2v-20ma-5v-lc-blue I have prepared a circuit as follows. I have used a distance sensor. Unfortunately, I obtain a ...
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Trouble using a generic 4-20mA to 0-5V board to connect transmitter to Arduino

I'm doing a big project, where I will connect a lot of sensors to my Arduino Mega 2560. Eagerly, I bought boards of this type, but I can't get them to give me any voltage output! I've connected them ...
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