Input: 4-24mA --> output 0-12V

[Mobz00]

Hi

I have a controller that gives me a 4-20mA signal.
Now I would to build something to convert that 4-20mA signal into into 0-12v.
That 0-12V will need about 5amp.
The 0-12v are running through the field windings in my alternator and it is there by creating a variable magnetic field.

I am on a low budget so it needs to be a cheap solution
Can someone give me an idea how to build such a system?

 

[johansen]

**broken link removed**

here, let me google that for you....

 

[Mobz00]

thank you for the reply!

I am a newbie to electronics so I cant design somthing like that myself. Do you knew where I could by a board like you are referring to?

 

[ChrisP58]

Are you expecting to get 60 Watts (5Amps at 12Volts) of power from your 4-20mA control signal? If so, there just isn't enough power to start with.

4-20mA control signals seldom have more than 24 volts behind them, and often much less. So, the most power that could be extracted from them would be less than 0.5 watts.

Now, if you have another source of power to supply the 60 watts, but you need to control it from the 4-20mA signal, then the link that johansen posted, plus a power amp, might do the trick.

 

[Mobz00]

yeah I figured that I would need a source of power to boost up the amps. But Chris does that power amp have a more common name? because I cant seem to find a place that sells them.
That circuit johansen posted do you knew if im able to buy that somewhere too?

 

[RichTheDude]

Eric Gibbs circuit may make a good starting point - https://www.electro-tech-online.com/blogs/ericgibbs/215-4ma-thru-20ma-loop-0v-thru-5v-converter.html , the voltage out could be used to drive a hefty driver.