What voltage is my house?
Almost all homes in the USA are single phase 120/240 volts.
Most homes in the United States are fed with single phase 120/240 volts. If you inspect your electrical panel, assuming it is not super warn and old there should be a sticker on the panel cover inside the door that will state the max voltage and amperage allowed. There should be no issues with common house hold items working on this voltage as almost anything you will buy for your home should work. If you buy an item from Europe you will need an adaptor as they run on a different voltage out there. If your electric device is made to work with a European electrical system you can easily identify this by the type of prongs on the device, which look much different than your standard US products.
VOLTAGE
When we say your home has 120/240 volts, that means that you have up to 240 volts for your home. Most things like outlets, lights and other basic items run off of 120 volts. When you see a breaker in your panel that is the size of two single breakers but has one single bar going across it, that is 240 volts.
AMPERAGE
Almost all houses will have the same voltage going to them, the difference is the amperage that you have available at your home. Typically your home should be fed with either 60, 100 or 200 amps. If you have a smaller home you should have either 60 or 100 amps, where as some bigger homes are supplied with 200 amps. The way to identify how many amps you have is to take a look at your panel. In your panel usually on the top of the panel ( but not always) there will be a breaker labeled MAIN. This is the breaker that is being fed from your electric service provider and this supplies all the power for your home. That breaker should say somewhere on the handle how many amps it is.
SINGLE PHASE
Homes are almost always fed with single phase voltage where as larger building or commercial spaces are fed with three phase power. Almost all house hold items take into account that the typical home has single phase power so you shouldn’t run into any issues with this unless you are looking into some heavier duty equipment in your home.
WHAT DOES IT LOOK LIKE?
A single phase 120/240 volt panel no matter the amperage should all look the same. Your electric service provider will provide a feed of electrical wires either from an overhead line or underground to a meter box. This can typically be located outside of your home usually right outside from where your panel is located on the inside. They will provide you with three wires, two “hot” wires as well as a neutral wire. The feed will go from your outside meter to inside you panel. The two “hot” wires will be terminated to your main breaker, these wires will most likely be two black wires but they could be black and red to identify the different phases. The third neutral wire will be terminated to a ground or neutral inside your panel. This wire is usually identified with a white color or it is just a bare wire coming from your meter. After the wires are terminated in the panel the main breaker is turned on the panel will be “live” and the individual breakers will receive power thru the internal copper bus that is in the panel.
In conclusion the voltage at your house should be the 120 240 volt that we spoke about above. The main difference between houses will be seen when you start looking at the amperage size that your electrical service provider is giving you. If after reading this article you are still unable to determine the voltage or your system or the amperage you have at your home, then contact a qualified electrician who will be able to determine this by opening up your panel. I hope this article provides you with a greater understanding of the electrical system in your home.