Where does this come from, and can I check it?

It compares the current going out with the current coming back. The figure is taken from International Electrotechnical Commission, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a everyday life fact?

Yes. It sits on the Everyday Life shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

A residual current device trips on unbalanced current

It compares the current going out with the current coming back Both supply conductors pass through a small toroidal transformer, and in a healthy circuit the currents are equal and opposite, so their magnetic fields cancel. If some current leaks to earth, the fields no longer balance and the induced signal trips the mechanism. A domestic unit typically trips at 30 milliamps within about 30 milliseconds. It sits in Mondo's everyday life collection, one of 200 facts that each trace back to the reference below.

Where this comes from

International Electrotechnical Commission

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: electricity, safety, homes

A residual current device trips on unbalanced current: the short answers

Where does this come from, and can I check it?: It compares the current going out with the current coming back. The figure is taken from International Electrotechnical Commission, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a everyday life fact?: Yes. It sits on the Everyday Life shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.