Sending 4-20mA Command Signal to a pressure controller

Hello,

I wonder if it is possible to use Arduino as a programmable logic controller (PLC) in order to control an electronic pressure regulator. The specification of the pressure regulator is listed as follows: Min Max Supply voltage 15VDC 24VDC Supply Current 100mADC 250mADC

Command Signal (Analog) Voltage 0VDC 5VDC Current 4mADC 20mADC

Command Signal Impedance Voltage 10k Ohm Current 100 Ohm

The regulator can be commanded either by current or voltage. It accepts 4-20mA signal or 0-5V analog and outputs 1 to 10 bar in pressure in a linear relationship. If I want to send 0-5V or 4-20mA command signal to the pressure regulator, is it possible to input the set point on the pressure regulator using Arduino?

"4-20mA command signal"....

A bit vague.

What protocol? Why not input the "set point" on the arduino?

I want to send 4-20mA command signal to an electronic pressure reducing regulator

Sending 4-20ma from an Arduino will require a signal convertor. Google "pwm to 4-20ma converter" for both commercial units and circuit ideas.

I want the pressure regulator to maintain a constant pressure at 3 bar.

That will require a PID loop. There is an Arduino library for PID.

I want to input the set point from my computer.

From your computer how? Serial? USB? Please be specific.

Johnny010: "4-20mA command signal"....

A bit vague.

What protocol? Why not input the "set point" on the arduino?

I need a programmable logic controller (PLC) to give command signal to control a pressure regulator. I was wondering if I can use Arduino as a substitute for PLC.

avr_fred: Sending 4-40ma from an Arduino will require a signal convertor. Google "pwm to 4-20ma converter" for both commercial units and circuit ideas.

That will require a PID loop. There is an Arduino library for PID. From your computer how? Serial? USB? Please be specific.

Thank you for the advice.

The pressure regulator accepts 4-20mA signal and output 0 to 10 bar in pressure on a linear scale. A programmable logic control should be able to do the job. But I wonder if I can achieve the same thing using Arduino. I want to use the serial monitor to input a pressure value. Let Arduino convert the value to 4-20mA signal and send it to the pressure regulator.

I know the Arduino will be connected to the PC using USB. I guess that I need to use serial pins to communicate with the pressure regulator. But I don't know how to do it yet.

I guess that I need to use serial pins to communicate with the pressure regulator.

No, you will use other digital pins to communicate with the 4-20 mA converter. The serial pins are used for program upload and to communicate with the serial monitor on the PC.

In order to control the pressure regulator (using the 4-20 mA converter) you will need to carefully study the instructions and information in the pressure regulator data sheet.

Hi, If this is an industrial pressure regulator then the OPs reg will be 4 to 20mA in to give 0 to 10Bar setting.

If you use a UNO the problem will be that it has no analog output, just a PWM output.

If you google UNO 4 to 20mA output

Many solutions to this problem will appear.

Tom... :)

jremington: No, you will use other digital pins to communicate with the 4-20 mA converter. The serial pins are used for program upload and to communicate with the serial monitor on the PC.

In order to control the pressure regulator (using the 4-20 mA converter) you will need to carefully study the instructions and information in the pressure regulator data sheet.

Thanks for the advice. I just got more info on the pressure regulator, could you take a quick look at it and let me know your thoughts? Thank you.

TomGeorge: Hi, If this is an industrial pressure regulator then the OPs reg will be 4 to 20mA in to give 0 to 10Bar setting.

If you use a UNO the problem will be that it has no analog output, just a PWM output.

If you google UNO 4 to 20mA output

Many solutions to this problem will appear.

Tom... :)

Thanks for the advice. I did more study on it. It seems like I need a current source and I could manipulate the current using PWM output from Arduino. I just got more info on the pressure regulator, could you take a quick look at it and let me know your thoughts? Thank you.