Hi!
I need a circuit design for measuring one of the AC line currents of a three phase system. The circuit MUST have the following charecteristics:

1. Must have a series electrical connection with the line. Not something like a magnetic field sensor etc.

2. Must provide a voltage output proportional to the current flowing through it. I need it to measure accurately upto 0.7-0.8 Amps.

3. Must not be a simple resistive circuit, as there are power and loading issues etc.

Please help. Thanks in advance.

 

Have you done any research? What, besides a resistor in series with the line, will satisfy condition #2? How do you expect to get around condition #3?

 

Hi!
I need a circuit design for measuring one of the AC line currents of a three phase system. The circuit MUST have the following charecteristics:

3. Must not be a simple resistive circuit, as there are power and loading issues etc.

Please help. Thanks in advance.

Since (1) is verboten then (3) is your only option. Just make R as small as you can. After all, that's what a Shunt does.

 

How about a one or two loop inductor and a hall effect sensor? The stronger the magnetic field, the more the current is present.