All right, I don't get it. I tried and tried, but I just don't understand. I have a dozen questions about this so somebody just pick one out all of these, I don't care.

What's inside a North American residential 240V pole transformer?

Is it (secondary) double iron core windings with 120V on each core and each end of the coil has one hot and one neutral wire that get tied in series to add up to 240V?


Is it a single iron core winding with two hot wires on each end and a center wire tapped at the 120th winding to make a 120V wire?

Are there two sine waves in a (secondary) double iron core transformer or one?


Are there two sine waves in a (secondary) single iron core center tapped transformer or one?

If either of the two types of transformers do truly have two sine waves, are they 180° opposite from each other at peak?


Are they 90 degrees out of step from each other at peak?


Are they on top of each other?

Please don't use to many equations or symbols, because I've exhausted my explanation abilities as it is with these questions and might not understand much more than the simple words that were already used here.


The power feed to a North American residence is normally provided by a center-tapped transformer, with the center tap of the transformer secondary grounded. the full secondary winding produces 240 Volts.

the connection is like so:


simulate this circuit – Schematic created using CircuitLab

Arghhh! The shcematic editor won't let me draw what I want!

The two ends or the transformer winding (120 V A and 120 V B) are each 120 Volts from Neutral, but 180 degrees out-of-phase, so you get 240 volts between them.

Most outlets in a home will connect between 120 V A and Neutral, or between 120 V B and neutral, so will get 120 volts.

Certain heavy loads (electric stove, electric water heater, electric clothes dryer) will connect between 120 V A and 120 V B to get 240 volts.


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