Current transformer on DC input (100A)

[theoldwizard1]

I am researching building a power inverter.  I think the answer is "No", but can a current transformer work on a DC (battery) cable ?

The obvious second choice is a shunt.

[macboy]

You are right, no current transformer for DC.

Shunt or Hall effect.

[Andy Watson]

No. A standard current transformer won't work with DC, but a Hall-effect sensor will. There are ready-made sensors available for current sensing - I can't recall the details at present, but searching for Allegro Microsystems should return some interesting results.

[theoldwizard1]

Okay, someone is going to have to explain how a "hall-effect sensor" measures current !

The one I am familiar with are for measuring rotational speed by turning a transistor on pr off in the presence/absence of a metal shudder.

[AG6QR]

Hall effect sensors sense magnetic fields.  A current (DC or AC) produces a magnetic field.  The biggest complication is how to make the sensors reject stray external magnetic fields while being sensitive to the induced fields from the current.

Wikipedia does a better job of explaining it than I could in a single post.

http://en.wikipedia.org/wiki/Hall_effect