urgent please

[eng.majeed]

Hello..
can any one say me how we can convert 4-20 ma signal output into differntial output voltage, related to transmitters.

 

[ericgibbs]

Hello..
can any one say me how we can convert 4-20 ma signal output into differntial output voltage, related to transmitters.

hi,
Use a 250R resistive load in series with the current loop.
This will give a voltage across the 250R of 1V at 4mA and 5V at 20mA.

OK.?

 

[ericgibbs]

hi,
This circuit will give a 0V to +/-5V differential output from a 4 to 20mA current loop.

Use a pot with a Vref source to give the -1V offset voltage, in this circuit the OPA's are CA3140's.

OK.?