I would like to know if there are any device which can compare current source like 5A(alternating) with a voltage source like 1V (alternating) and give me an output. If not, which circuit I should make to have this?

 

Normal people compare similar items. They compare apples to apples, oranges to oranges. Current is not voltage. Voltage is not current. There is no point comparing them.

 

Normal people compare similar items. They compare apples to apples, oranges to oranges. Current is not voltage. Voltage is not current. There is no point comparing them.

Ok and there is a device where I compare only current sources signals? I want to measure 50A to compare with 20A, lets say. Its analog to op amp comparator for voltages, but instead voltage I wanna current.

 

It probably exist.
It is easier to run current through the resistor. That generates voltage across the resistor. Then you compare voltages. 1 volt is equal to 1 ampere through 1 ohm resistor. Basic physics.

 

If this is main's current then you will isolation, such as by using a current transformer to generate a voltage to the current, and isolate the voltage from the current.

 

If this is main's current then you will need isolation, such as by using a current transformer to generate a voltage to the current (the part in bold makes no sense to me), and isolate the voltage from the current.

I know it is late/early.

 

... A wattmeter multiplies alternating current times alternating voltage times the cosine of the phase difference angle, giving watts. However, they usually only work with a standard frequency such as 60 hertz.

 

I know it is late/early.

I meant to generate a voltage from the current.

 

If this is main's current then you will isolation, such as by using a current transformer to generate a voltage to the current, and isolate the voltage from the current.

Hi

Or you can use an "RMS to DC" converter chip that provides isolation.

eT

 

Hi

Or you can use an "RMS to DC" converter chip that provides isolation.

Is there such an animal?

 

I would like to know if there are any device which can compare current source like 5A(alternating) with a voltage source like 1V (alternating) and give me an output. If not, which circuit I should make to have this?

Thinking of e.g. MOSFET VGS to IDS curves, not sure but maybe with a graph with an -X and X and a Y axis? Someone far smarter than I am could figure out how to plot that with code and any computing device from a Pi to a datalogger or similar. Would take a while to consider how to put together analog interface as I've never even considered such a circuit.

 

Is there such an animal?

Yes...a few manufactures make them.

Here's one;

https://www.allegromicro.com/en/Pro...p-Integrated-Conductor-Sensor-ICs/ACS723.aspx

 

Yes...a few manufactures make them.

Good to know.
Thanks.