Detect current in a wire

Hi, there this idea which is brewing in my head for a while now. I was wondering if there was a way which I could detect current through a wire using arduino like a clamp on meter, and here is the catch - how to detect current through and IEC cable. I know clamping the hot and neutral wire will give zero reading.
Any help is greatly appreciated
Thanks in advance

Define an "IEC cable".
How much current, and is it DC or AC?
If AC, what frequency?

  • how to detect current through and IEC cable. I know clamping the hot and neutral wire will give zero reading.

I don't know any way of doing that, since the magnetic field will cancel-out. (For "non-contact" current sensing with the Arduino, a Hall effect sensor is sometimes used, and sometimes a current transformer. Either way, you may have to tap-into the AC power line (even though there is no direct-electrical connection to the Arduino).

Since an IEC cable has a standard connector, you could make an inline plug-in adapter.

"The magnetic field cancels itself out" is a rather broad description of what actually happens. On the surface of a wire-pair the fields are discrete and opposite as each wire produces its own field based on the direction of current flow. When considered as a pair the sum of the fields is indeed zero, but if you locate a field detection device against the side of a cable you will detect a field proportional to the current flowing.

There are clamp-on devices specifically designed to clamp onto flow-and-return cables and are capable of measuring current flow by sensing the 'outer' field created.

Hall sensor should work, it be closer to one of the wire.
Clamp can work also, cancellations is occur when all phases are in balance which is rare in real world.

Thanks for the response guys! Here is my idea basically. Lets say I have an electric kettle and I want to get a message or some kind of notification when the water is boiled. The idea is to detect when the current draw stops or is reduced indicating the task has completed.
Ideally I don't want to modify the kettle or tap into the mains socket. The best idea I could think of is to use a hall - effect sensor but I'm quite sure that having the hot wire and the neutral wire at close proximity would not work....

Build and intermediate box with the cores separated. Box connects to wall socket, kettle etc connects to box

Kettle probably already has an LED that turns off when done. Hell you could even just monitor temperature.
Playing with mains when you're struggling to do something so simple does not give anyone a good feeling.