20v dc convert to a ajustable 4 to 20 ma signal

Hi, i need to convert a 20v dc + to a 4 t0 20 mA variable signal
can you help please
thank you
Collin

 

Collin,

How do you want to vary the 4-20mA level? Are you trying to create a 4-20mA output transducer? Or, is this to be a test signal to check a 4-20mA receiving device?

Ken

 

Hi bill. the project is to test controllers on the air compressors as a simulator. the origenal layout is a 20v dc + (one wire) running to an air
pressure transducer. this converts to a 0 to 20 mA signal. (one wire return) the idea is to simulate the air transducers. i want to use the 20v + from the controller and vary the 4 to 20 mA signal ( if possible). the controller converts the 4 to 20 mA signal to airpressure reading.as a result i can test the controllers alarm and cut out settings.

 

Here is an adjustable constant current source, along with a DVM, should serve your purpose.

Ken