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I need to convert a signal from 0-5 volt to 4-20ma. How can I do this?

if you have siemens plc system u select input module 0-5 volt analog voltage i.put selection and get the calculated value in words to get exit from 4-20 mA analog out module.

other vise you need real convertor of V - mA.check in internet lot of different sourse are available to buy...
thank you sir...

i am sankaranarayanan..
Mumbai.
sankar_29kw@yahoo.com

If the device needs power then this will do the job converting a resitsnce to 4-20. It will power up a resistance device and produce a 4-20 out.

http://www.almegcontrols.com/4-20_converter.htm
and you have 4-20.

Thanks,
Bob Hogg

You can use a converter from Phoenix Contact. Visit the website http://www.phoenixcontact.com

Evandro Vizicato
evandro.vizicato@uol.com.br

You are kidding right? i mean, use a resistance for god sake, how do you convert voltage to current? that's electronics basic.

good luck.

Well, a resistor will work when going from 4-20 ma to 1-5 volts. But it won't necessarily work going the other way. Current loop transmitters are designed to drive a load that can vary from application to application, from 50 ohms to 750 ohms, typically. A current transmitter is able to compensate for the addition or deletion of a loop instrument by using more or less power to drive the loop. A fixed-size resistor could not do this and voltage sources are not designed to power current loops. Voltage sources expect a high impedance measurement device to be attached.

A 250 ohm series resistor should do the trick.

That will give them 0-20 ma not 4-20ma. Look at converters from someone like Weidmuller or Phoenix Contact.

Contact Pepperl+Fuchs..Model KFDx-DCV. Dip switch selectable voltage input and dip switch selectable output.

http://www.am.pepperl-fuchs.com/pdf/pa/documents/KFDX-DCV_Configur ation.pdf

Phoenix Contact has a transceiver for this purpose, contact your local dealer.

Please send us your e-mail. I will forward an e-mail with circuit voltage to 4..20mA.

Let using IC: AD693, AD694 or using this simple cir:
http://www.delabs-circuits.com/png_circuits/arc20060212.html

Good luck! ^_^