Shunt resistance VS Rogowski Coil in current measurement , which one is better?

Shunt resistance VS Rogowski Coil in current measurement , which one is better ?

Just for reference I want to create small circuit that measure the power , so which one I go for ?

UPDATE 1 : I'm measuring AC current Isolation is required Scale of current will be A to hundreds It will be a permanent part of the circuit

I'm going to make an Electrometer

Answer

Rogowski coils measure only AC current. If you're measuring DC power, they are 100% not applicable to you. I've made use of several Rogowski transducers in my workplace, and have found that the coils can be quite fragile.

Shunt resistors can be used for AC or DC current measurement. For AC applications, it can be preferential to use a current transformer instead of a shunt, as it introduces less losses in the circuit under measurement (assuming your single-turn primary is of sufficient size).

Hall effect sensors are good for AC or DC as well, but the ones that I've used need + and - DC biasing, and can be cost-prohibitive at lower power levels.

Given your range of current, I suggest that a hall effect sensor will be your best bet in terms of accuracy, size and losses.