I am fairly new to the forum and have noticed on several threads people that might need a little help understanding what is referred to as “split phase”. In fact is it just simply that the secondary winding of the power transformer has a wire connected in the middle of the winding so that it “splits” the output in half. You can use the entire winding for 240v or either half for 120v. It is not more complicated than that.
I found some web pages that might help if this is still not clear.
Understand first a bit about generators. As a north pole passes a coil of wire, there is also a south pole doing the same thing on the opposite side of the rotating element inside the generator. Together, they create the voltage difference on the two output wires.
https://www.allaboutcircuits.com/worksheets/ac-generator-theory/
More helpful than understanding generators is to understand what a voltage divider is. Voltage divider principles apply to resisters in series, capacitors in series, inductors in series, batteries in series, and yes, transformer windings. Don’t let the formulas run you off. Just look at the photos and see if they help.
https://www.electronics-tutorials.ws/dccircuits/voltage-divider.html
And with a better understanding of the basics, transformers fit the same principles. I picked this page on multi winding transformers because it is pretty helpful to see all of the different tings you can do with a multi winding transformer. Some transformers have 2 primary windings that can be connected in series (like for 240v input) or in parallel (120v input). Also if you have two secondary windings, you can connect them in series for higher voltage and the same current or in parallel for the same voltage and higher current. Or you can swap ends with the wires, hook them up in “parallel” and short the thing out because one is opposite of the other one. Note the dots on some of the drawings, showing the polarity orientation.
https://www.electronics-tutorials.ws/transformer/multiple-winding-transformers.html
Anyway, hope this might help someone. The web site https://www.electronics-tutorials.ws/ has a lot of tutorials that look fairly good.
Dan Thames
I found some web pages that might help if this is still not clear.
Understand first a bit about generators. As a north pole passes a coil of wire, there is also a south pole doing the same thing on the opposite side of the rotating element inside the generator. Together, they create the voltage difference on the two output wires.
https://www.allaboutcircuits.com/worksheets/ac-generator-theory/
More helpful than understanding generators is to understand what a voltage divider is. Voltage divider principles apply to resisters in series, capacitors in series, inductors in series, batteries in series, and yes, transformer windings. Don’t let the formulas run you off. Just look at the photos and see if they help.
https://www.electronics-tutorials.ws/dccircuits/voltage-divider.html
And with a better understanding of the basics, transformers fit the same principles. I picked this page on multi winding transformers because it is pretty helpful to see all of the different tings you can do with a multi winding transformer. Some transformers have 2 primary windings that can be connected in series (like for 240v input) or in parallel (120v input). Also if you have two secondary windings, you can connect them in series for higher voltage and the same current or in parallel for the same voltage and higher current. Or you can swap ends with the wires, hook them up in “parallel” and short the thing out because one is opposite of the other one. Note the dots on some of the drawings, showing the polarity orientation.
https://www.electronics-tutorials.ws/transformer/multiple-winding-transformers.html
Anyway, hope this might help someone. The web site https://www.electronics-tutorials.ws/ has a lot of tutorials that look fairly good.
Dan Thames
